On my systems, Rls 5.0 and Rls 5.5, the Ctrl OAM with admin2 username/password works. (but PDT does not??) Make sure the admin2 and pwd are defined in LD17 under PWD. In hindsite, check that you are using octopus cable NTBK48, port 0 connected to the COM RS232 port on back of the shelf where the MGC card resides.