OCS: Certificate for local system with Thumbprint .... is about to expire or already expired.

Suddenly certificate thumbprint events where appearing on our Office Communications Server and several users reported that they are unable to login to OCS.


After logging in to the OCS server and adding the Office Communications Server 2007 MMC snap-in to the console I noticed the certificate used was expired at 4/4/2013, which was yesterday. This is visible in Standard Editions(depending on which edition used ofcourse) >  <server-name> > <server-fqdn pool> > General settings.

The certificate is used to encrypt SIP communications over TLS, so all clients use it to communicate with the OCS server.

To solve it a new certificate needs to be requested, this can be done by Right clicking the server pool > Certificates > Create a new certificate. The rest off the wizard depens on how your PKI is configured or company procedure. I choose Send the request immediately to an online certification authority > (Ofcourse information in the images is environment specific)




















Create a request to a certifate authority, probably you internal CA and issue. Afterwards you need
to run the wizard again and import the certificate pending request.

  

 

 

 

 

 

For more information about OCS and Certificates:
http://www.ocspedia.com/Certificates.htm

 

For more information about PKI and CA:
http://technet.microsoft.com/en-us/library/cc779826(v=ws.10).aspx