From what I have been told when you access an application Domino adds up the length of all the names of groups that a person is a member of. If this value is less than 64kb all is fine, if the value is close to 64kb and the application has additional Domino Security roles, this may tip the scales and take the value beyond the limit. Please note that I have added an alias to the groups in hierarchical format (we will be implementing xACLS), we have over 7000 groups. First is their any technical information on this, also is there a way you can out how many groups a person is in and the total group name size. Many thanks.