Diagnosis
Either the object is being processed by another user and is, therefore,locked to ensure consistency or else you do not have the systemauthorization required to carry out the action required for the objectin question.

System Response
The authorization concept of the ABAP/4 Dictionary checks theauthorization according to the following criteria:
authorization to carry out a specific action
authorization to edit a specific object type (for example, TABL orINDX)
authorization to edit objects assigned to a specific development class

Procedure
If the object is being edited by another user, the system sets a lockthat is released when editing of the object is complete. You can thentry again to edit the object.
Check your authorizations and, if necessary, contact the systemadministrator responsible.