the answers here are correct, but more information might prove helpful, so here it is...
When you get these Event ID's in Event Viewer Application Log:
6000: The winlogon notification subscriber was unavailable to handle a notification event.
6001: The winlogon notification subscriber failed a notification event.
6005: The winlogon notification subscriber is taking long time to handle the notification event (CreateSession).
6005: The winlogon notification subscriber is taking long time to handle the notification event (Logoff).
6006: The winlogon notification subscriber took xxxx second(s) to handle the notification event (CreateSession).
6006: The winlogon notification subscriber took xxxx second(s) to handle the notification event (Logoff).
Open Group Policy Editor
Start\Run\gpedit.msc
Computer Configuration\Administrative Templates\System\Scripts
Set the following:Specify maximum wait time for Group Policy scripts: Enabled (Options: Seconds, 60)
Run logon scripts synchronously: Disabled
Note: Max wait time set to 60 seconds or whatever you are comfortable.
