Should I Demote to Fix Replication?

I have a follow up question to my earlier post regarding domain controllers
that have become out of synch and have passed the "tombstone" period and so
will no longer replicate with each other.

It was suggested that I change a registry setting to allow for replication
between "corrupt partners."

I only have two DCs, and we are a medium-size organization (maybe 300
users). Would it be better simply to demote DC2 to a non-DC, and then
re-promote it to a DC? Or is it a better and safer solution to follow
through with the registery change?

Thanks,

(Also, is there any way to back up the user accounts to a file or
something?)



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