VOfm tcode

Hi,

I am trying to maintain 'VOFM' tcode, but its giving the message that 'Object 'TFRM' cannot be blocked, it will be displayed' and not allowing to maintain the new entries. I have checked the lock entries in SM12,but there are no lock entries found. Still it is giving the same error. Please advice, it is urgent.

Rgds,

Khadeer.