They implemented the group-membership cache in order to make the execution of the script faster (a lot less query on the windows token, as the query is made every 30 days instead of at each logon). So if I force the update of the cache at each logon with the "-f" parameter, it should mean my script will execute slower.
But for my 1800 user who execute the kix32.exe from the netlogon, the logon script is not slower if I force the update at each logon.
So I prefer force the update at each logon (= solved my problems) than having trouble with the INGROUP (and others) function for new or modified NT groups.
For your drive mapping, it seems a bit complicated like you do. You should use CASE SELECT or INGROUP and GOTO functions. Everybody use it like that. But maybe you have some requirements I don't know...
Just an information, there is a new Kix version 4.10, but it is an Alpha release. Maybe it is better not to use it in a working environment. Don't know why it is not clearly written.
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SAVE THE WORLD - PROTECT THE PLANET