out of curiousity is this for a program called CLCS III?
The problem usually resides in the system.ini file
I haven't dealt with btrieve in a long time but do remember that most btrieve apps require for a btrieve section be added to the system.ini file. Copying files and reinstalling files doesn't generally work.
These are the files you may want to check however:
BREQUEST.EXE v6.16.1 for DOS applications
WBTRCALL.DLL (38K) v6.15.4 for 16-bit Windows applications
BTRCALLS.DLL v6.15.1 for 16-bit and 32-bit OS/2 applications
WBTRV32.DLL v6.15 for 32-bit Windows NT/Windows 95 applications
Workstation utilities, including Roll Forward and DOS Requester utility (BREQUTIL)
THese files and a patch to these files can be obtained from the pervasive ftp site. You can get there from:
http://www.pervasive.com/support/technical/papers/migrate.tml
Hope this helps