Diagnosis
You attempted to open a Web interface for processing. But the Webinterface is already being processed by another user.

System Response
The Web Interface is opened in display mode and cannot be changed.

Procedure
Try to open the Web interface at a later point in time. Proceed asfollows to find out which user is locking the Web interface:
Go to Lock Management (transaction SM12).
In the selection screen, enter the table name UPWB_MDATA and thecurrent client. Leave all other fields blank.
Choose List.