There is around 450 groups on the domino database. However, I found that some groups are not connected (i.e. unused) with any database.
Is there any method that I could find out which groups are not necessary (has no entry in any databases) ?
Subject: How to find out dangling ACL groups?
Our company has a 3rd party product to find unused groups.
It will look in the following places to determine if a group is used:
For mail and multi purpose groups: Scans the MTSTORE.NSF (message tracking database)
For ACL, multi purpose, and server groupsL
Scans ACLs of all databases
Scans form readers and form users in all forms in all databases
Scans view readers in all views in all databases
Scans reader and author fields in all documents in all databases
You can download a free trial version from http://www.helpsoft.com
Subject: How to find out dangling ACL groups?
Well actually our Workflo!ACL Manager will do the tough part of the job, and that is to find which groups do have access to a database. The view of ACL Entries by User Type will show each group and which DBs it has access to and what the level of access is. Now you would have to manually compare that to the Address Book groups.In the same view is a grouping called Unknown and this lists people/groups/etc that exist in the database ACL but not in the Address book. So you can give it a try, download the demo from our site at:
http://wfs.com/workweb/wfsweblib.nsf/Src/DocSet*Notes+Net07
it is an inexpensive tool that can save you hours of admin time.
Subject: RE: How to find out dangling ACL groups?
One thing to keep in mind is groups in readers fields, that are not specifically in an ACL (Default = author). I have run into this before cleaning up groups
Subject: RE: How to find out dangling ACL groups?
Thanks lot.
Unfortunately my boss does not approve me to buy the license. 
I think I have to write the agent by myself :(…
Subject: RE: How to find out dangling ACL groups?
Writting the agent to do that is not really tough, however, you will probably spend more time than the $250 to buy the product, but then I’m prejudiced. 