Rudy,

First thanks for posting the sp. The code it generates uses sp_dropuser and that does not work for usernames that contain periods. One of the applications we use creates usernames in the following format: vdb_First.Last

EXEC sp_droplogin vdb_First.Last

results in:

Msg 102, Level 15, State 1, Line 1

Incorrect syntax near '.'.

Looks like you need to enclose your output like you did with the sp_dropuser:

PRINT 'EXEC sp_droplogin ['+ @SpecificName +']'