A: Windows programs cannot be “converted” to run directly in the Mac operating system, which is called Snow Leopard. But, if you use virtualization software like Parallels or VMware fusion, and install Windows, then a Windows program like Microsoft Outlook can run simultaneously with your Mac programs. Technically, you are running it in Windows, but the two operating systems are active at the same time. With both of these virtualization products, you can even hide the entire Windows desktop, so that the Windows program you are running simply occupies a window on your Mac like any Mac program does. You don’t even notice that Windows is running.

In the case of files you created in Windows, the situation is even simpler. Most of the common types of files consumers use—including Microsoft Office documents, MP3 music files, MP4 video files, JPG picture files, text files, Adobe PDF files, and others—can be run in native Macintosh programs without conversion and without the need to run Windows programs. So you can just copy them to the Mac side and use them in Mac programs like iPhoto, iTunes, or the native Mac version of Microsoft Office, which uses the same file formats as the Windows version.

If you have an unusual or proprietary Windows file for which there isn’t an equivalent program on the Mac, you would run it in a Windows program, as described above.

If I am planning to upgrade a Windows XP machine to Windows 7, can I buy the upgrade copy of 7 or must I buy the full version?

A: According to Microsoft’s Web site, XP is one of the older versions of Windows upon which you can indeed indeed use the less expensive upgrade versions of Windows 7. The company’s online store says: “All editions of Windows XP and Windows Vista qualify you to upgrade. So, if you’re running either on your PC today, buy a package labeled ‘Upgrade’.”

I’ve been holding out (for what feels like forever) on purchasing a Netbook because I read that Apple was coming out with one. Can you tell me anything about when they might really begin selling them?

A: Apple executives have said repeatedly and emphatically that they don’t plan to offer a netbook, which is essentially a cheap, small laptop. Instead, Apple is widely believed to be working on a small slate or tablet device that would be controlled via a fingertip touch screen. This would be sort of like a larger iPhone or iPod Touch. The company hasn’t confirmed that such a product is in the works, but many analysts and Apple bloggers predict it will debut early next year.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital web site, http://walt.allthingsd.com.

I saw your column last week saying Apple’s MobileMe now does a better job of syncing contacts, calendar items and email. But will it allow me to sync to my iPhone directly from my company’s corporate calendar, address books and email?

MobileMe is meant for consumer data, not corporate data. Essentially, Apple’s own servers act like a company’s servers in order to bring corporate-style push syncing to consumer data that isn’t kept on corporate servers. To sync your corporate contacts, calendar items and email to an iPhone, you would use a different built-in option in the iPhone: Microsoft Exchange. Assuming your company’s IT department certifies the iPhone as an acceptable device, and your company uses Exchange, as many or most do, you can use an iPhone to perform instant two-way syncing of corporate contacts, calendar and email. It works just like a BlackBerry or Windows Mobile phone in this scenario. I have tested this, and found it worked well.

Is it possible to sync a Treo or BlackBerry using MobileMe? If not, how can I transfer my Treo contacts and calendar items to the iPhone?

While MobileMe is agnostic when it comes to computer platforms, working on both Windows and Macintosh computers, it is single-minded when it comes to handheld devices. It synchronizes data only to Apple’s own iPhones and iPod Touch devices. It doesn’t work with the Treo, the BlackBerry, or any other smart phone or handheld device beyond those made by Apple. One simple way to move contacts and appointments from Treo to iPhone is to use Outlook as an intermediary. First, sync your Treo to Outlook. Then, just plug your iPhone into your PC, launch iTunes, and sync the iPhone with Outlook. The data from your Treo should then be on the iPhone. MobileMe isn’t required.

I can’t find the location of the files contained in my Personal folders in Outlook that contain my contacts and saved emails. Can you help?

To find the location of the single combined Outlook data file that contains your email, contacts and calendar, follow these steps. First, select “Data File Management” from the File menu. A window will open showing the name of your data file, which includes its location on your hard disk. Click the button to the right that says “Open Folder,” and you will be in the folder that contains this file, with the file’s name or icon highlighted. Outlook data files use the extension “pst” at the ends of their names.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

I need some help sending videos to others. It seems that every video I try to send in various ways is always too large. I’ve tried to use a program that works with Outlook to compress the email attachment, but it’s always still too large. Is there a solution other than uploading them onto YouTube or something similar?

I suggest you try one of the services that specifically exist to transmit files that are too large for email. They typically work by having you upload the files to their servers, which, unlike YouTube, don’t expose them to the world. Seconds after you upload these files, your recipients receive an email that includes a specific link to the file you uploaded. The email is small because it includes only the link, not the file itself. The recipient clicks on the link, and the file is downloaded to his or her computer.

The service I use for this is called YouSendIt, and can be accessed at yousendit.com. It works in all the major Web browsers, and on both Windows and Macintosh computers. The company has a free plan that covers files of up to 100 megabytes in size, and allows each file to be downloaded up to 100 times, or up to a gigabyte of total downloads each month. For $10 a month, you get a maximum file size of two gigabytes, 500 downloads per file, and a monthly maximum limit of 40 gigabytes.

In my experience, YouSendIt works well. It can be used directly from within a browser, or via a small program called YouSendIt Express, that lives on your computer and handles large files faster than the browser version does. YouSendIt also offers an Outlook plug-in that can automatically route large downloads via the service rather than through regular email, though I haven’t tested this plug-in.

Our daughter is heading off to college this fall. She will be an art/graphic-design major, and the school recommended that she buy an Apple MacBook. I’m not sure if she should get what the college calls the “midlevel MacBook” or the “advanced MacBook.” The only differences are a slightly faster processor, a hard disk that is 40 gigabytes larger, and a “SuperDrive” for CDs and DVDs rather than a “Combo” drive. The price difference is $90. Which should we buy?

Either machine would be fine, and a lot depends on your budget, since college itself is of course very expensive. But I think, in this case, the extra $90 would be worth paying. This has nothing to do with the processor speed, which she probably wouldn’t even notice. But, if she is going to be creating a lot of graphics files, which can be large, the extra hard-disk space could be important.

The same goes for the CD/DVD drive options. The “SuperDrive” is Apple’s term for a drive that can create both DVDs and CDs, while the “Combo” drive can create only CDs. (Both drives can play both types of disks.) For someone who is producing large files, the ability to create DVDs can be handy, since DVDs have much higher capacities than CDs.

My laptop has been infected by rogue viruses, posing as antispyware programs, that I can’t get rid of. When I go on Google, I find a number of sites that claim to offer free software that will get rid of them, but I am reluctant to download anything onto my machine from a source that I am not sure of. What’s a reliable program that will do that job?

I would immediately buy a genuine, legitimate commercial antispyware program, install it and run it. The best ones I know of are Spyware Doctor by PC Tools, at pctools.com, and Spy Sweeper from Webroot, at Webroot.com. Each costs $30, but that price can save you a lot of heartache.

You can find Mossberg’s Mailbox, and my other columns, online, free, at the new All Things Digital Web site, http://walt.allthingsd.com.

We are connected to Comcast (CMCSA) cable and use no antennas. Will we need one of the government-subsidized converter boxes next February?

Not if you are using a cable set-top box, like the vast majority of cable customers. If you are one of the minority of cable households whose TVs use an internal cable tuner, you may need a converter box. To be sure, contact your cable company or TV manufacturer.

In your laptop buying guide last week, you recommended buying a machine equipped for the “n” type Wi-Fi of wireless router. I was under the impression that this has not yet been standardized. Is that wrong?

The engineering committee that has been debating the standard for years has not yet completed its work, but the market has simply moved ahead on its own. This new, faster version of Wi-Fi is being built into routers, computers and other devices by nearly every major manufacturer. In my limited tests, I have found no compatibility problems, and it is backwards compatible with the older “g” and “b” standards.

Is the Mac immune to viruses? If not, do you have a recommendation of the type of antivirus software one should procure and load onto a Mac?

No personal computer or personal computer operating system of which I am aware is “immune” to viruses, spyware or other malicious software. That includes Apple’s (AAPL) Macintosh and its operating system, Mac OS X Leopard. Hackers have demonstrated the ability to invade the Mac. However, there are only a handful of viruses or other malicious programs for the Macintosh that have successfully spread beyond the lab. And these have harmed only a small number of actual users.

Of the well over 100,000 known viruses, spyware programs and other malicious software applications that are about in public, all but this handful are written to run on Microsoft (MSFT) Windows, and cannot operate on the Macintosh OS. For that reason, I don’t believe Macintosh owners need security software, unless they install and run Windows on their computers. If they do run Windows, Mac owners are well advised to purchase and install Windows security software to protect the Windows portion of the machine.

Having said that, I do not mean that Mac owners should be blind to security threats that don’t involve viruses or spyware. Just like Windows users, Mac users can succumb to what is called “social engineering” — scams and schemes that operate via email and Web sites that are often authored by crooks but made to look official. So, like Windows users, they must be on their guard.

You can find Mossberg’s Mailbox, and my other columns, online free at the All Things Digital web site, http://walt.allthingsd.com.

I have a new H-P (HPQ) laptop and there are several preinstalled media-playing interfaces that have been foisted on me. Do I really need all of these interfaces? Can’t I just get all of this media to run through Windows Media Player or iTunes?

Since you weren’t specific, I don’t know what media software came with your new laptop. I’m sure some of it may have been redundant “craplets” — the unwanted software PC makers load onto their machines in order to collect a fee from the programs’ publishers. And you are correct that many of the most common audio and video file types can be handled by Windows (MSFT) Media Player and iTunes.

However, the Internet is full of media file types that are best played, or can only be played, in specialized software — either separate applications on your computer or online players that are enabled via your Web browser. So, over time, most users will collect additional players, or plug-ins for their Web browsers, that will supplement their main media-playing program. One way to see if the media software on your new computer is necessary is to test what types of files it handles. If you can open and play these same files in Windows Media Player or iTunes, and you prefer to do so, then you probably don’t need the added software.

If I am running Windows Vista on my iMac desktop using Parallels, will Apple’s Time Machine backup program automatically preserve the Windows hard disk, too?

Yes. Parallels, and its competitor, VMWare Fusion, create virtual Windows hard disks inside a Macintosh. When you are running Parallels or Fusion, Windows sees these virtual hard drives as if they are distinct physical disks. However, they are in fact just very large files on your Mac’s hard disk. So Apple’s (AAPL) Time Machine backup program treats them like any other file and backs them up. Time Machine can also restore these virtual Windows hard disks, in their entirety, just as it can restore other kinds of files.

There are some caveats, however. Time Machine treats each virtual Windows hard disk as a big, unified blob of data, so it cannot peer inside them to recover individual Windows files you may have accidentally deleted while running Windows programs. Also, if your virtual Windows hard disk is large, and it changes often, then using Time Machine to back it up may suck up a lot of space on your backup drive, as numerous archived versions of the file accumulate.

I currently have a DVD player and a large stack of DVDs that I play through my analog TV set. After the 2009 digital TV conversion, will I still be able to use my existing DVD player and play my existing DVDs, even if I buy one of the government-subsidized converter boxes?

The FCC says DVD players and other add-on gear “will continue to work, even if they are only analog-capable.” But it adds that “manufacturers are producing a number of different connectors to hook equipment together and improve picture and sound quality. Check with your equipment retailer to determine the types of connectors that will work with your equipment.”

In other words, while there’s no inherent conflict, it all depends on your particular DVD player, your particular TV set, and how you have them connected. The best thing to do is consult closely with the dealer or manufacturer selling the converter box so that you understand how it can coexist with your current DVD player setup, or how you might have to alter your current setup.

You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

There’s no other major item most of us own that is as confusing, unpredictable and unreliable as our personal computers. Everybody has questions about them, and we aim to help.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability.

Last week you discussed how to uninstall Windows Vista and go back to Windows XP. But I own a Macintosh, and after upgrading to the new Leopard operating system from Tiger, I find I dislike Leopard. How can I uninstall Leopard and go back to Tiger?

To restore the older Tiger operating system after upgrading to Leopard, you should first find the Tiger DVD that came with your Mac. Insert it and reboot your Mac while holding down the “C” key. This will boot the computer from the DVD rather than your hard disk.

On the screen that shows available hard drives for installation, click on the Options button and select the “Archive & Install” option. Also, select the choice called “Preserve Users & Network Settings.” If you have enough free disk space (roughly six gigabytes), Tiger will be reinstalled and your home directory and applications should be preserved.

However, just as with Windows, performing such an operating system “downgrade” on a Mac can be tricky for a nontechnical user. You might want to hire an expert to do it. If you do decide to try it yourself, I strongly urge you to first read an Apple document that contains more details, including some potential pitfalls and limitations of the “Archive and Install” procedure. It’s at http://docs.info.apple.com/article.html?artnum=107120.

Occasionally, I try to download a song or artist that would be in the “Easy Listening” category, but neither iTunes nor Amazon lists that genre. How can I find them?

In the iTunes store, there is indeed a genre called “Easy Listening” that contains thousands of tracks. The problem is that it’s not listed on the front page of the store. To find “Easy Listening” and the songs it contains, select “Browse” from the box labeled “Quick Links” at the upper right on the store’s front page. Then click “Music” in the far left column and “Easy Listening” in the column labeled “Genre.”

In Amazon’s MP3 download service, I couldn’t find a listing for the “Easy Listening” genre. But some of the songs and artists you’re looking for could be listed under other categories. Try directly searching for an artist’s name or a song title in the search box at the top of the MP3 Downloads page.

Why isn’t a FireWire port included on either of the two new slim laptops you recently reviewed, the Lenovo ThinkPad X300 and the Apple MacBook Air?

Both laptops are so small that they can only include a limited number of ports, though the Lenovo has many more than the Apple. And standard FireWire, also known as “1394″ or “iLink” on some machines, is becoming redundant in mainstream consumer computers, since the USB 2.0 ports offer roughly the same speed and are compatible with many more devices. There is a faster version of FireWire, which Apple uses on most of its desktop models. But there is also a faster version of USB in the works.

You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

Corrections and Amplifications

Due to incorrect information provided by the manufacturer, this column erroneously says that Macintosh users performing a “downgrade” from Apple’s new Leopard operating system to the older Tiger system should select an option called “Preserve Users & Network Settings.” In fact, that option isn’t available when installing an older version of the operating system over a newer one. Users must instead manually relocate their data files and settings after performing the downgrade, a process that is explained at this Web page: http://docs.info.apple.com/article.html?artnum=107297.

I couldn’t find any columns on products you recommend for monitoring kids’ Web access and installing parental controls. I recently purchased a new computer for my 9-year-old daughter. I want to make sure she can only access specific Web sites and I want to protect her from inappropriate spam and chatting.

If you have a computer running one of the newer versions of Windows or the Macintosh operating system, I recommend using the extensive parental controls that are now built right into those operating systems. While you can never underestimate the ingenuity of computer-savvy kids, these built-in controls, if properly used, are generally harder to evade than the ones provided by third-party software.

I did recently review these built-in parental controls, which appear in Windows Vista, and in the Tiger and Leopard editions of the Mac’s OS X operating system. You can find that column at: ptech.allthingsd.com/20070614.

I want to switch to a Mac, but my life is on Microsoft Outlook, which is only available on Windows. Is there a simple way to convert all of this data to programs on the Mac?

There is a $10 program that performs this task. It’s called O2M (Outlook to Mac) and is from a company called Little Machines. It can be downloaded at littlemachines.com, where you also will find details about the Mac programs with which it works. This is a Windows program, which transfers your Outlook data into files you copy to your Mac. You then manually import these files into your Mac programs.

According to the company, the program exports Outlook email, email attachments, contacts and calendar appointments and allows you to import this data into Apple’s built-in email, address book and calendar programs, as well as into Microsoft Entourage, and other third-party programs.

Another approach is to install Windows on your Mac, and keep running Outlook. If you do this using the Parallels or Fusion virtualization programs ($80 each, plus the cost of Windows,) you can run Outlook simultaneously with your Mac programs.

Does the new version of Microsoft Office for the Mac work on pre-Intel Mac models?

Microsoft says it does, though I didn’t test it on one of these older machines. According to Microsoft, the new Office 2008 runs on any Mac “with an Intel, PowerPC G5, or PowerPC G4 (500 MHz or faster) processor.” However, you also need a relatively recent version of the Mac operating system, either the new Leopard edition, or the latest update (called 10.4.9) of the Tiger edition.

You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Do I need antivirus or antispyware software on a Macintosh running the Leopard operating system?

The Macintosh isn’t inherently invulnerable to malicious software. In fact, last week it was reported that there is a new scam on the Web that can plant a malicious “Trojan horse” program on the Mac. However, this is a rare event. There have been practically no viruses, spyware or other malicious programs written for the Macintosh that have actually spread outside the laboratory.

For that reason, most Mac users don’t run security software, and security software companies don’t make much of an effort to sell it for Macs. I don’t believe it is necessary, so far, for all except the most paranoid (and those who run Windows on their Macs). In fact, freedom from the burdens of running and updating security software has been one of the Mac’s big advantages.

Even the new Trojan Horse apparently relies on tricking the user, rather than on sneaking through holes in the Mac operating system. According to reports, to get infected you must go to a pornography site, and agree to download a program allegedly needed to view the porn. Next, the Mac will require that you type in your administrator ID and password to complete the installation, thus agreeing to install the program a second time. If you do all that, you get a program that supposedly redirects your Web browser to bogus Web sites. My advice: even if you frequent porn sites, don’t agree to download any programs from them (that goes for Windows users as well).

Some interpret the appearance of this new Trojan Horse as a sign that the Mac’s increasing market share will begin to attract a flood of viruses and spyware, and that Mac users will soon have to start running security software. If it happens, and the threats are more insidious than the latest one, I will be ready to change my recommendation. But not yet.

In reply to a question last week, you mentioned that there are free security programs available for Windows. Could you please suggest where to download such alternatives?

There are a number of them, but ones that I like are free, basic antivirus and antispyware programs called AVG from a company called Grisoft, which also makes more elaborate security software. You can download these programs at free.grisoft.com/doc/5390/us/frt/0.

I don’t have Microsoft PowerPoint but I occasionally get PowerPoint files as email attachments. Somewhere I read that one can download a free PowerPoint program so you can read these files. Can you help me with this, please?

I don’t know of any free versions of PowerPoint, but Microsoft does offer a free program that will let you view, but not create or edit, PowerPoint files. You can download it here.

You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Write to Walter S. Mossberg at mossberg@wsj.com

I currently spend about $50 to $60 per year for Norton Security software. Is this necessary when Windows XP has its own security built into the operating system?

Windows XP doesn’t include antivirus or antispyware programs, so you definitely need some sort of add-on security software. If you don’t want to pay for it, there are free alternatives available.

How do we determine when to purchase a new PC? Our current Dell is about five years old. I’m feeling a little worried because I have my music and photos on the computer and don’t want to lose them.

There’s no universal answer to your question. In general, I don’t believe people should replace computers that are working well for them just because they reach a certain age. On the other hand, five years is pretty old for a PC. At that age, the odds increase that the hard disk may develop problems, and that newer versions of the software you like will require hardware upgrades that may cost more than you want to invest in an older machine.

Assuming your Dell is working fine, that you aren’t a power user, and that your music and photo activities are simple and basic, there’s probably no urgent need to replace the PC. But, to assuage your concern about “losing” your pictures and music, you might back up those precious files to an external hard disk or an online backup service.

Last week, you compared the start-up time of Windows Vista to Apple’s new Leopard operating system, and found Vista to be much slower. But you used different laptops for each. What would the numbers be on the same Macintosh running the two operating systems?

I ran the tests again on a single computer, a fairly new Apple iMac, which can be started up, and restarted, in either Vista or Leopard. I used the Mac’s Boot Camp feature, in which only one operating system is running at a time, has its own dedicated portion of the hard disk and fully controls the hardware. The machine uses an Intel processor and other key components commonly found on Windows machines, and runs Windows just like a Dell or any standard Windows PC, without any involvement from the Mac operating system.

This Vista installation doesn’t include any of the speed-robbing trial software commonly included by PC makers, though it does have security software from Symantec. However, the test results were very similar — Leopard started and restarted much more quickly than Vista did.

In this simple test, I timed both operating systems from a cold start and a restart until the computer was fully ready for operation, with the hard disk quiet and the network connection established. The cold start, beginning with the computer completely off, took Leopard 46 seconds, but took Vista one minute and 42 seconds. A restart, beginning with the computer running an email program, the Firefox Web browser, and Microsoft Word, took one minute and two seconds for Leopard, and three minutes and 17 seconds for Vista.

You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Write to Walter S. Mossberg at mossberg@wsj.com

Apple makes beautiful hardware, and, in my experience, it runs Windows quite well. In fact, the mouse and keyboard problems you cite are easily overcome, since you can plug almost any USB keyboard and mouse made for Windows into a Mac and they will work fine, right-mouse button and all.

However, what makes a Mac a Mac is primarily Apple’s OS X operating system, and the software Apple bundles with it, the iLife suite. If you don’t intend to use that, I don’t see much point in buying an Apple computer. You won’t get the advantage of the Mac’s lack of viruses and spyware, which stem from the operating system, not the hardware. And you can buy a Windows computer for less than the least expensive Mac.

In my view, the main value of the Mac’s ability to run Windows is that it allows Apple owners to use the few Windows programs they require or prefer that lack Mac equivalents, while primarily running the Mac operating system and programs designed for it.

How can one send an email to a group of people without all of their individual email addresses showing?

The most common method is to put your own email address in the “To” field and the names of all the recipients in the “Bcc” field, which is designed to be invisible. There’s always a danger someone quickly scanning just headers will decide not to read the email, since it isn’t addressed to her, but most email veterans understand the technique.

Is there a way to regain the traditional drop-down menus and other interface items in the new, redesigned Microsoft Office 2007?

There is at least one third-party add-in program designed to do this, but I haven’t tested it. It’s called Classic Menu for Office 2007, and can be found at www.addintools.com.

You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Write to Walter S. Mossberg at mossberg@wsj.com