Diagnosis
A lock requested by calling an ENQUEUE function module cannot begranted because a different SAP transaction is already holding thelock.

System Response
The ENQUEUE function module triggers a corresponding exception. If thisexception is not trapped by the application program, it causes thecurrent SAP transaction to be terminated automatically.

Procedure
Check the lock table to determine which user or which transaction isholding the requested lock (Tools -> Administration ==> Monitor -> Lockentries). If necessary, contact this user.