I get the error when I try to enter a malformed value for the price field (such as when I purchased Canadian chips for canadian currency - I enter a C$5.00). Usually the program gives me the error and aborts, and a restart fixes it. The FAQ at http://www.k-c-enterprises.com/cm/faq.htm lists this as the issue and work-around.

I am wondering if your database got corrupted. My first suggestion is to get the program running again. Do an uninstall, and then remove the directory (probably in C:\Program and Files\Checkmate by default). Then reinstall the program without your database.

This should work, if it doesn't you have a different problem and should probably stop there. The next step is to check the database. There are two ways of doing this, first - you can email (if it is not too big) to someone who can try it out. Second, you can use Microsoft Access 97 to check it out (do not use Access 2000 or Access 2002 to attempt to fix it as it will "upgrade" the database and cause the database not to work with Checkmate).

There are some utilities available on the web that will aid in repairing/compacting the database. LMK if you need additional help.