SAP Message 0S049 - Error & reading lock object &

Diagnosis
An error occurred reading the lock object. The error numbers mean thefollowing:
1 -> object_not_found
2 -> object_not_specified
3 -> permission_failure
4 -> type_not_valid
5 -> others.

System Response
Program processing continues after the error message.

Procedure
Ensure that the specified lock object exists. To do this, you can useTransaction SE11. It may also be useful to reactivate the lock object.