All of the major digital maps contain erroneous information about our street in Virginia, and don’t even show several new streets near our home that were built over three years ago. I infer that there is one source of cartography used by these Web services, and also by my Garmin navigation system. But I can’t find out what it is. How can an individual get something like this corrected?

There are actually two main companies that make the underlying maps that most of the navigation-device makers and digital-map sites use. One is called Tele Atlas (TLATF.PK), and one is called Navteq (NVT). Garmin (GRMN) uses Navteq. Each mapping company has a Web page where users can report errors or changes.

For Navteq’s error-reporting Web page, go to navteq.com and click on “Map Reporter.” For Tele Atlas’ similar page, go to teleatlas.com and click on “Report Map Changes.”

In reading your review of the new Gogo in-flight wireless Internet system, I wondered about two things: Does it support “virtual private networks,” and when will it be installed on Amtrak trains?

While I didn’t test this, Gogo’s maker, Aircell, says that VPNs, which are used by many big companies, do indeed work over the service.

As for Amtrak, the Gogo system wouldn’t work for trains, because its antennas point up, into the sky, and don’t cover ground locations like railroad tracks. However, if you are on an Amtrak train in an area where cellphone towers are near the tracks, and your laptop computer or cellphone can pick up cellular data signals, you can already surf the Web and do email and other online tasks on the train.

In fact, I happen to be writing this column on an Amtrak Acela train between Washington and New York, and, using a Verizon (VZ) laptop card, my laptop is able to access the Internet with only occasional lapses.

Because of problems I had with my computer, I lost my Internet Explorer favorites. How can I save them so I can easily restore them if they get wiped out again?

There are several methods. You should, of course, be backing up all your key data, including your browser favorites or bookmarks, regularly, either to a local external disk, or to an online backup service. That would create a fairly fresh backup of your favorites. You could also use one of several Web sites that specialize in hosting, and sharing, bookmarks or favorites. They allow you to add bookmarks to your online list as you surf, and also to upload and download the favorites and bookmarks you keep locally on your computer. The best known of these sites is probably del.icio.us, which is at http://del.icio.us.

The simplest method, however, is probably to just export your favorites to a file and save it in your Documents folder, on your desktop, or on a USB thumb drive. You can then use this file to restore your favorites in case of disaster. To do this in the latest version of Microsoft (MSFT) IE, click on the “Add to Favorites” button, select “Import and Export,” click “Next,” then click “Export Favorites” and walk through the steps that follow. Detailed instructions for all versions of IE are at: support.microsoft.com/kb/211089.

• 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.

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 Cingular data networks, the quality of Compaq laptops and options for connecting an iPod to home speakers.

In your review of the new T-Mobile BlackBerry Pearl, you said Cingular Wireless has a data network that is much faster than the EDGE network that T-Mobile uses. But I have a BlackBerry from Cingular and it, too, uses EDGE. So how is Cingular faster?

In 80 cities, Cingular has now rolled out a new network based on a technology called HSDPA that, in my tests, can be 10 times as fast as EDGE. However, most of its phones and digital devices haven’t been updated in new versions that can use the new, faster network. So far, only a few regular phones and laptop data cards from Cingular can use HSDPA. Its data-centric hand-helds, like BlackBerrys and Treos, are still stuck on EDGE, which Cingular continues to maintain alongside the new faster network.

But Cingular plans to offer new versions of the data devices in the coming months that can take advantage of the new, higher speeds. By contrast, T-Mobile has nothing faster than EDGE. Verizon Wireless and Sprint also have networks that are much faster than EDGE, based on a technology called EVDO. They are way ahead of Cingular in both the number of cities deployed and in the variety of devices that can use the highest speeds. For instance, the Verizon Treo I carry uses EVDO and can download Web pages and email attachments much more quickly than any EDGE device can.

There is a catch. With Verizon, Sprint and Cingular, even if your phone or data device can use the highest-speed networks the carriers offer, they will drop down to a lower-speed network if you enter an area where the higher-speed coverage isn’t available.

I bought a Compaq laptop in January 2005. Now in August it will not turn on. Naturally I only had a one-year warranty. The Geek Squad tells me I need a mother board, and that will cost more than a new laptop. Does Compaq have a history of only lasting a little over a year, or did I get a lemon?

Neither my email from readers nor anything I have read suggests that Compaq computers typically last only a year or so. However, reader surveys published by Consumer Reports and PC Magazine rank the Compaq brand (which is now owned by Hewlett-Packard) at or near the bottom in categories like how often its laptops need repairs and how reliable they are.

In general, I believe that as the factories in China (where nearly all laptops are made) jam more powerful and numerous components into slender laptops, quality and reliability are falling. Even Apple, which ranks at or near the top on the surveys I mentioned, is having problems with some of its newest laptops (and I am not referring here to the burning batteries Apple and Dell purchased from Sony).

Are there any good, effective options for getting an Apple iPod to work with a home speaker system? I guess I’m envisioning a “receiver” that allows an iPod to dock with it.

There are lots of products on the market that allow you to connect an iPod to a home audio system, or even just speakers. They range from simple audio cables you can buy at Radio Shack to iPod docks that connect to speakers or an audio receiver, and even wireless approaches. Apple itself makes a $19 cable and a $39 dock for this purpose and also sells a complete kit, with dock, cables and remote, for $99. But other companies sell similar products as well as self-contained docks.

There are way too many of these to list here, but there are some Web sites that can help you. Apple has a Web page listing some accessories, at www.apple.com/ipod/accessories.html. More are listed at Apple’s online store, at store.apple.com, under iPod Accessories — “Cables & Docks.” Another good source for information about this topic is ilounge.com.

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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

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 waiting for the new Mac OS, using an iPod with an old version of Windows and getting broadband in rural areas.

I am planning to replace my aging Dell desktop with one of Apple’s iMac machines. Now that Apple has announced that the new OS X Leopard will be released next spring, is it advisable to wait for Leopard’s release to buy a new iMac? Or will the current iMac be able to run Leopard when it is released?

If history is any guide, an iMac you purchase now, or in the next few months, should easily be able to handle Leopard, which is the sixth version of Apple’s Mac OS X to be released since 2001. Since Apple upgrades its operating system far more often than Microsoft does, the upgrades tend to require less of a jump in hardware capability. (Microsoft’s forthcoming new version of Windows called Vista, due in January 2007, is the first major overhaul of Windows since 2001.)

However, Apple hasn’t promised that every new feature of Leopard will run on any iMac sold now, and the company has coldly cut off users of older models in the past. So, if you can wait, do so. It’s always better to buy new machines with a new OS preinstalled, even though Apple’s OS upgrade process has generally been much quicker and more reliable than Microsoft’s. Another benefit: Apple typically charges existing users $129 for an upgraded OS, even if their machines are only, say, six months old. But new Macs next spring will include Leopard free of charge.

Even if you can’t wait until spring (you said your Dell was “aging”), consider waiting a few months to see if Apple brings out a new iMac with Intel’s latest processor, the Core 2 Duo, which is faster and more efficient than the Core Duo in current iMacs. I have no information that this will happen, but you should know by November or so.

I’ve got a new iPod I want to use with my Dell Dimension 4100 running Windows Me, but the iTunes software will apparently run only on XP or 2000. What’s my best bet for software to load files onto my iPod?

Try a product called XPlay 2, by Mediafour. It is specifically designed to work with older versions of Windows, including Windows Me. It costs $30 and can be downloaded at mediafour.com/products/xplay/. There is a free trial, but it is limited.

We live on a dirt road in rural Virginia with no cable and can’t get DSL. How can we get broadband? We would prefer not to do a satellite connection because you still need a phone modem to send material. Is there some kind of fast wireless connection we could get from our PC to our ISP? I see laptops with wireless antennas sticking out of them around here and they must transmit to somewhere.

Satellite Internet access has improved, and no longer requires a dial-up modem for the return path — in fact no use of the phone line is needed at all. Of course, as with any satellite service, your house must have a clear line of sight to the area of the sky where the particular satellite you use is situated. For more information, see www.hughesnet.com.

Another option, if you have good cellphone coverage, is a broadband cell-phone modem. It uses the cellphone network to connect you to the Internet at speeds roughly comparable with a slow home DSL line — which is still much, much faster than your current dial-up connection. This is probably what all those laptops with antennas are using.

These cellphone modems, using a technology called EVDO, are offered by Verizon and Sprint, and Cingular is slowly building a similar wireless broadband capability. For more information, see the Web sites of the phone carriers.

In some parts of the country, but not Virginia, a company called Clearwire is offering wireless broadband to rural homes.

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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