I may not be using the correct Windows terms here, but I believe the
account needs to be a member of the Windows local administrator group.
If NetApp_DFM\administrator is not in the local administrator group,
try adding it. Then you'll need to log out of OpsMgr webUI and log back in.
If you do a 'dfm user list' from a command window on the Windows box,
does it list the user ?