Hi @DymekPL ,
> The problem appears after some time (about 2 weeks) when I want to add another location.
Did you mean add a new subscriber to merge replication? Then the replication sync failed?
Please share us more related error message from replication monitor as below screenshot.
The error message that you offered is a general error message. You can maximize the history logging by selecting 3 for the –HistoryVerboseLevel property of the Snapshot Agent and Merge Agent as below screenshot. The more log information you will have, it will be better to find out and identify the merge replication problems.
To enable detailed logging by the Replication Agent. You will need to stop and restart the Replication Agent for the setting to take effect.
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