Unable to access Btrieve Apps

Recently installed Client 3.3, Novell 5.1, SP 2a, and GW 5.5, SP2. Now users are unable to access Btrieve applications. (The server is running Pervasive Btrieve 7.51)

What files need to be loaded under the Windows/System directory in order for the Windows 95(B) workstations to enable Btrieve apps to work?