I have been having trouble for a while now with two DCs in the same site not synchronizing the sys vol share. The two DCs in question are in our head office site. DC1 holds all 5 roles (PDC, FSMO etc etc) DC2 is the one with the problem.

There are NO errors being logged in FRS at all. I have run authoritative restores and non authoritative restores, each time they seem to complete because event ID 13516 is logged but still there is no replication. Active Directory replicates changes almost immediately so there is full connectivity. I have also made sure that the NTFRS change journal is set at 512MB.

Both servers are DNS servers and they point to themselves as the primary server, they are also GC servers. ACL on the sysvol share looks good as well, it is the same on both servers. We have another 7 sites and the sysvol share replicates fine between all of them, all the DCs in other sites replicate with DC1.

Is there anything else i can check? i really need to fix this. thanks.

Run replmon and force a replication, and that should show you if it's actually working or not - and if not, why.

I know this is crazy but ... just rebuild DC2. You said it was just acting as a DC. What level is the domain? Also, I would suggest splitting up some of the FSMO roles... hope this helps...