My IT department will not turn on the feature in our servers that would allow me to receive corporate email on my iPhone. This has forced me to revert back to my BlackBerry Pearl. Can I transfer my iTunes music to my Pearl?

It depends on what you mean by “iTunes music.” If you mean music you bought from the iTunes store in protected format — which describes most of the store’s catalog — the Pearl can’t play it, unless you go through a laborious multistep process to convert it to unprotected files. If you mean unprotected music that is managed by the iTunes program on your PC, the Pearl can handle it as long as it is in open formats supported by the Pearl, including the MP3 or open AAC formats.

To get these files into your Pearl, simply use the music-transfer software that came with the Pearl to copy the songs from your computer’s hard disk to either the Pearl’s internal memory or to a flash memory card you may have in your Pearl.

I recently purchased a new iMac with the Leopard operating system, and have installed Windows Vista on it as well, using Leopard’s Boot Camp feature, so the Mac can boot into either OS. I would like both of those operating systems to share an external hard drive so I can back up my files. Is it possible to do that?

Yes, provided you follow one of two scenarios. The first would be to format the external drive as a Windows drive, but be careful to use the Windows format called “FAT32,” not the one called NTFS. Out of the box, Macs can see all Windows drives and can read from them all. But they can only save files to Windows drives that use the FAT32 system for organizing files. The downside of this is that the FAT32 system only allows files of up to 4 gigabytes each.

The other scenario would be to use a Mac-formatted external drive, which doesn’t have that limitation. Of course the Mac operating system can handle such drives perfectly, but Windows can’t even see them. However, in your Vista setup, you can install a third-party Windows program called MacDrive 7, which allows Windows to both read from, and write to, Mac-formatted drives. I have tested it successfully with Vista under Boot Camp on an iMac. The $50 program can be downloaded from mediafour.com.

The hard disk on my new Sony VAIO laptop is filling up fast. It is trying to get me to watch a lot of movie trailers. Is all that video stored in my machine somewhere and if so can I dump some of it out?

If your Sony laptop is like mine, not only are the unwanted movie trailers pre-loaded on your hard disk, but so are the entire movies, which Sony actually charges you to watch. In my case, these files took up over 4 gigabytes of precious disk space. This is a particularly outrageous example of what I call “craplets,” unwanted trial software that litters new Windows desktops. You can delete these files and reclaim all that disk space without any harm to your computer.

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

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. This week my mailbox contained questions about using cellphones as modems for laptops, storing personal files from office computers and buying an ultralight laptop.

I would like to buy one of the new phones that run on high-speed networks from Verizon or Sprint and use it as a modem with my laptop. Do the phone carriers charge extra for this?

Yes, both Sprint and Verizon do impose an extra monthly charge for using this feature of phones like the new Treo 700p. They reason that if you access the Web on your phone, which has a limited browser and no hard disk to store large downloads, you aren’t likely to use a huge amount of network capacity. But once the phone is used as a modem with a laptop, it becomes very much like their laptop cards, for which they do charge a hefty monthly data fee. For instance, Sprint charges $40-$50 a month extra for unlimited data connections using the Treo 700p as a modem, depending on the length of your contract and whether you also have a Sprint voice plan.

I’m changing jobs after 10 years. What is the best way to take my personal files with me? I know Microsoft Office documents can be readily put on any storage media, but what about emails and contacts stored in Outlook? Can you offer some advice on how to best accomplish this move? (I am not taking any company property.)

Since this isn’t a legal column, I won’t weigh in on what constitutes personal data on a company computer. But it’s pretty easy to move your email and contacts from your Outlook to another copy of Outlook on a new PC at your home or your new office. In Outlook, go to the File menu. Select “Import and Export… “. Choose “Export to a File.” Then select “Personal Folder File (.pst).” Next, choose the Outlook folder containing the data you want to export. This could be your email Inbox, or any other email folder, or it could be the Contacts folder, or any other non-email folder, like Calendar. Finally, select the location where you want to save the exported data. If you are using a USB drive, use the “Browse” button to locate it. Then, hit “Next” and then “Finish.” Repeat the process for each folder you want to export. At the new computer, insert the drive with your exported data, launch Outlook, bring up “Import and Export…” again, and this time select “Import from another program or file.” Follow the steps to import a .pst file.

I am interested in purchasing an ultralight laptop computer for traveling, something I could carry in a messenger bag. I wish to use it mostly for Internet connectivity and word processing. I might even sneak in a DVD for use on the plane. I have looked at the Sony Vaio TX series and the Dell X-1. Are there others in the same size/weight category I should consider?

Yes. You might look at the HP Compaq nc2400 or the Lenovo ThinkPad X60 or the Gateway NX100X or the Toshiba Portégé R200. Except for the HP, none of these has an internal DVD drive, though, so depending on how important that is to you, you might have to spend more or go up to around four pounds. The Sony TX is excellent and combines low weight with an internal DVD. But it’s expensive. Other options for ultralights with internal DVD drives are offered by Fujitsu and Panasonic. I haven’t reviewed all of these, so I can’t recommend them all. My review of the Sony TX is at: http://ptech.wsj.com/archive/ptech-20051006.html. My review of the HP nc2400 is at: http://ptech.wsj.com/archive/ptech-20060518.html. My review of the ThinkPad X60 is at: http://ptech.wsj.com/archive/ptech-20060420.html.

* * *

Because of the volume of email I receive, I can’t routinely answer individual questions by email, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

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