LYNC REPLICATION NOT WORKING

In a Lync Deployment, where we have installed Lync Edge Server, we see the Replication is not healthy. You will notice a red cross or in the Management Shell the Replication is not UpToDate: False.

If actually have telnet to the Edge Servers Port 4443, you realize that the port is open and working.
As well you can test access the service itself:
https://<edgeserver.fqdn>/replicationwebservice

Via this access, you also be able to validate the assigned internal Certificate and the Certificate Chain. If you encounter an error with trusted root certificate, you will end up adding it other Trusted Root Authorities.

Afterwards, you will still encounter the red cross, or false up-to-date status.

This is normal!
The Replication itself is working fine, but your Connectivity to the Edge is limited.
This mean we cannot query the service due to the SECURE CHANNEL limitation.

Solution:

Open REGEDIT
navigate to:

HKey_Local_Machine\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL

add the new DWORD:
ClientAuthTrustMode Value=2

Now reboot the edge server. After it has restarted, you might need forcing the CMS to replicate:
Invoke-CsManagementStoreReplication

Problem is now solved...!

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Documentation:

Validation:

Set new Registry Key on Edge Server:

Do not forget the reboot.

Verification: