Whats the maximum number of groups a user can be a member of in a 2003 domain ? I have users that are members of 1,000 + groups that started to get the error : 'During a logon attempt the user's security context accumulated too many security ids' I have implemented the Cred SSPI fix to set the token size to 65,535 but some uses with a large group membership cannot logon until I remove some groups. Is there a way round this ? If this resolved in 2008 R2 domain and forest level ? Thanks