Hello, 

For the last two months I constantly get on my Lync servers  the following error message: 

In the past 30 minutes the server received 87772 invalid incoming certificates. The last one was from host 10.92.2.254.
Cause: This can happen if a remote server presents an invalid certificate due to an incorrect configuration or an attacker.
Resolution:
No action needed unless the number of failures is large. Contact the administrator of the host sending the invalid certificate and resolve this problem.

Event ID Lync server: 14366

I checked the certificates for my Lync servers, but  they are valid for long time. I checked whom belongs to that IP in the message. Found that belongs to load balancer 's responsponsibles, but the guys there says the LB certificates are valid and the following: " Because every user access will be source natted by the load balancer it is possible that the certificate errors will be caused by the Lync users"

What do you think? How the users could cause this kind of error message in the Lync servers? Is this possible?

BR.

Anyta

Hi,

Please re-ran step 1"Install Local Configuration Store" and step 2 Setup or Remove Lync Server Components then assigned a new certificate using the certificate wizard on FE Server and Edge Server. Then test the issue again. It is better also assign a new HLB certificate as well.

Best Regards,
Eason Huang