Office Communicator clients cannot communicate with contacts homed on AOL

 

Summary:

If your organization leverages Public Internet Connectivity (aka: "PIC") in conjunction with their Live Communication Server 2005 and/or Office Communications Server 2007 servers, you may not be able to successfully communicate with (or see the presence status of) America Online Instant Messenger users.

Explanation:

America Online changed their root certificates on their SIP Access Gateway at approximately 12/2/2008, 4:00 AM EST.

Resolution:

The America Online Root CA 1 certificate, which can be obtained from https://pki-info.aol.com/AOL/, needs to be in the trust list of all Live Communication Server 2005 and/or Office Communications Server 2007 servers (that connect to sip.oscar.aol.com) by 12/2/2008, 4:00 AM EST.

More Information:

Microsoft Customer Support Services has created a Windows Media Video to walk our customers through the process of adding this certificate.