>When I attempt to pack a table, I get the message FPT file missing or invalid. Other that this message, the table works in the application and the memos can be accessed. Is there a way to repair this file?

There are several commercial and free utilities that can fix this. Here on the UT downloads section you can find:

ATFixDbfFpt 1.5a, all xBases supported. File #9930

and

Crashed tables rebuilder File #9264

and

FoxFix from www.xitech-europe.co.uk

Make a backup of the files before you start!