We have been having issues for few months now with the odd computer being very slow to get to the logon screen.
In the past it was sitting on Please Wait... since enabling Verbose vs Normal status messages to see where it exactly hangs
It seems to be stopping on.
"Applying Group Policy Local Users and Groups policy..."
The problem has been very miner as in only effecting random one or two computers a week and not always the same computer.
, just so happened it effected 8 computers that where required for exams this afternoon.
I will continue to investigate just though if someone has had similar issue and what they found to resolve it.
Does event viewer give you any clues?
We've had this issue, wasn't always Users and Groups like yours, sometimes they would get hung up on other group policy preferences. I'm not sure we've seen the last of it but certainly managed to improve the situation.
Basically did two things, went through the relevant GPO's with a fine tooth combs checking for any thing it could be getting stuck on. Such as wrong paths and non-working scripts. Second was enabling 'logging and tracing' on a particular suite, which I think is a 2008 R2 feature. (Policies>Admin Temp>System>Group Policy>Logging and tracing). Then after a machine has done a 'slow' boot you can look in the client logs (C:\ProgramData\GroupPolicy\Preference\Trace\). They don't make easy reading but the key thing was seeing which policy's were getting processed and then checking the timestamps to see what was taking a long time.
If you haven't already it would be worth using 'Group Policy Results' in the 'Group Policy Manager' on a problem PC. This might flag up some policy processing issues.
Hope that helps.