Well, -1601 is a Jet internal error that means "The key was not found in any
record". For synchronization this usually means a query in replication
system tables (since they are the only tables which are queried during a
sync that can cause an error when something is expected but not found).
You can look at MSysReplicas in one (or better yet all!) of the farm members
and see if the replica in question was marked as removed for some reason --
if it was then it would explain the error.

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MichKa [MS]
NLS Collation/Locale/Keyboard Development
Globalization Infrastructure and Font Technologies
Windows International Division
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> Indirect replication between partials and farm has been working fine
> for 2 years. I now see the following message in the synchronizer log
[quoted text clipped - 9 lines]
>
> Thanks