Can’t find DC !!!

I have a DC at site 3 which went offline for some reason. I rebooted it but it can’t find or bind to a DC. NTFRS went offline since it ca’t rteplicate with the other DCs. I get a 1000 usr error saying no DC to log onto. Active Directory can’t be reached on this dc. I checked microsoft site but it said take server or workstation off domain and join again but this is a dc and if it can’t replicate it sure won’t depromote itself.
I can open my network places and see and open other workstations.

Any ideas?