It may only be a problem with the memory card, not the scanner itself. And the fact that you were using a new laptop might have something to do with it if you went to a new operating system. Is the computer that was previously used to program the scanner still available?
http://forums.radioreference.com/gre-scanners/209170-psr-800-error-code.html
http://forums.radioreference.com/gre-scanners/209170-psr-800-error-code.html