Subject "Open Database xxxxx failed" Creating Odbc DSN for Firebird 1.5

Trying to create an odbc DSN for a .gdb database on firebird 32bit. the os is windows 7 32 bit and the odbc driver is Firebird odbc 32bit. Database connection is successful in iBExpert but the connection to the firebird service manager fails when testing for connection in IB Expert.Odbc DSN is also failing with the error "Open Database xxxxxxx failed" Please help