Hi @Anonymous ,
From the article:ALTER LOGIN
You cannot use ALTER LOGIN with the DISABLE argument to deny access to a Windows group. For example, ALTER LOGIN [domain\group] DISABLE will return the following error message:
"Msg 15151, Level 16, State 1, Line 1 "Cannot alter the login 'Domain\Group', because it does not exist or you do not have permission."
so what was your operation at that time, whether made the same error?
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