Q My ISP offers 5MB of storage to each customer. Since my Web page doesn't use half of that, I decided to create a backup directory under my main directory on the ISP's Web server. Now I regularly back up critical spreadsheet and word processing documents to it. Most ISPs back up their Web servers once a week, which makes them fairly safe for off-site storage.

A This is a great idea, but certain cautions spring to mind. First, my ISP, highly reputed though it is, has lost my Web site twice in the past year, both times restoring it from backups that were more than a few weeks old. As a business owner, I would not trust backups of critical files to a computer outside my control ù or to a business I am not paying specifically to safeguard my files ù for more than 24 hours.

There's also a security issue. Depending on how your ISP sets up file and directory privileges on its server, Web surfers may be able to read and download your files. For absolute privacy, encrypt the files with Phil Zimmermann's Pretty Good Privacy utility (a freeware version is available at www.nai.com/products/security/pgpfreeware.asp and on our cover CD). You should also store your files in a directory other than your Web directory, which is publicly readable. But even a non-Web directory may be read by the public. Again, it depends on how your ISP configures file privileges; talk to its techies to find out.

If you decide to store files in your Web directory, make sure you've created an index file for the directory. An index file (often named index.html) is the default Web page that anyone who accesses the directory without typing a more specific URL will see. If you don't provide one, then instead of a Web page, visitors will see a list of files in your Web directory ù any of which they can access.