Is there a limit to how many records can be in a file that is the source for a grid?

I have hit a brick wall at 32768 records in a certain table. I thought it was a
corrupted table, and ran it thru a recovery program to no avail. I have recreated the
table from scratch and stuffed it with blanks, leaving a few to spare. I add these in the
program, but as soon as it hits the magic number of 23768 I get an error message
saying 'Table number is invalid'.

The program has been running for 10yrs without a hitch, so nothing has changed
in the code, or anything...

Any help will be MOST appreciated!

Thanks!