SAP Message AD040 - & is reserved for &

Diagnosis
Both an active and a revised version of the selected object exist. Therevised version is locked by another user, so you cannot obtain updateauthorization for this object. This is not a temporary system lock(i.e. the user is currently maintaining this object), but a permanentreservation of the revised version.

System Response
Since an active version of the object also exists in addition to therevised version, the active version is displayed with a messageexplaining that the revised version is locked.

Procedure
Only the user currently maintaining the revised version can remove thislock by activating it, resetting it or explicitly releasing the objectfor maintenance by all other users with the 'unlock' function.