I'm noticing in the Application event log every 30 minutes I get a warning from MSExchange OAuth Event ID: 2008.  When retrieving metadata from the url 'https://lync-fe.domain.com/metadata/json/1', different certificate(s) have been found.

The only thing we did in Lync is renew the certificates so our internal CA would regenerate them in SHA256 keys.  I checked on the Exchange server and our domain root CA cert for our SHA1 and our new SHA256 root certs are in the Trusted root store for the computer.

I checked in Outlook Web Access and I can still sign into Lync and see presence information.  I would just like to eliminate this warning that is in the logs every 30 minutes and ensure a healthy deployment.

Thank you!

Same problem here, hope someone knows the answer

bump - seeing this as well. the URL references our old Lync 2013 server which has been decommissioned and replaced with Skype for business servers with new names...