Two suggestions:
First: at the old style (before VFP and Tableupdate()), with a while loop trying to lock the record/table with a try time and an On Key Label ESC to exit the loop and make a tablerevert.
If you are using transactions do a rollover if fail

Second: at the new style try a while loop with tableupdate(.F.) and check for returned value from tableupdate,... the same than first answer.

Hope this help

Mauricio