what's wrong - domain controller or different source?

what's wrong	possible source	solution
time unsynchronized	pdc role domain controller	verify if pdc is synchronized with external time source verify if dc are synchronized with pdc
users can't login	time synchronization (Kerbers) 802.1x issue	check domain controllers if they are synchronized are certificates ok for 802.1x? crl are available?
users change password issues	pdc role availability	maybe something wrong is with pdc role dc?
can't join a new computer to domain	limit per user account of new computers availability of RID master	increase limit check if RID master is available - dc don't have rid pool to assing
can't create new objects - uses, groups, computers	availability of RID master	check if RID master is available
universal group membership failure	infrastructure master global catalog availability	infrastructure master is not updating links between domains because is on global catalog check if global catalog is available