I have recently upgrade a client's machine from a 9500 to a G3 running Panther so it will network nicely with the rest of the office (Windows and OS X boxes). It doesn't need to do much, but one of the things they use it for is to run a couple of Filemaker databases for clients and such. However, after importing the old FM3 databases into FM7, it prompts for a user and password or gives me the option to view the database as a guest. The original databases weren't password protected. Can someone suggest a solution? Thanks for any help you can provide.

Have you read the migration docs on the Filemaker web site? It specifically talks about the new security applied to converted files.

http://www.filemaker.com/upgrade/techbriefs.html

Summary: on conversion, the old password becomes both the username and password in the converted file, and passwords are now case sensitive.