Question : The Certification Authority Service has not been started.

I am attempting to install MS OCS 2007 R2 on a Windows 2008 server in a Windows 2008 AD environment. When I try to sign in with the Communicator client I receive the following error:

"There was a problem verifyng the certificate from the server. Please contact your system administrator."

I found this post on Experts Exchange that was pretty much identical to my issue: http://www.experts-exchange.com/Software/Office_Productivity/Office_Suites/MS_Office/Q_23408390.html

I attempted to follow the MS article referenced even though it was targeted for Server 2003.
http://technet.microsoft.com/en-us/library/bb735413.aspx

I can get to the https:///certsrv web page, but when I click the "Download a CA certificate, certificate chain, or CRL" link, I get the following error:
"An unexpected error has occurred: The Certification Authority Service has not been started."
When I look in Services I can see that certsrv.exe is indeed running.

Is there some place in Windows 2008 Ad that you have to authorize the CA root services much like you do DHCP or DNS?

Not sure where to go from here. Any help appreciated. Thanks.

Answer : The Certification Authority Service has not been started.

No, it creates its own area in the AD Configuration during installation.

You can try restarting certificate services and see if that helps.

You can also try this command ran from the CA: "certutil -vroot"
This will recreate the web pages and fixes things a decent amount of the time.

If that still doesn't take, reboot the CA server.

If you are just trying to get to the root certificate chain, the CA certificate should be stored on the CA in %systemroot%\system32\certsrv\certenroll  directory.  If you have multiple CA servers (e.g. root CA and subordinate CA) you should get the cert for at least the root, but sometimes it helps to get the cert for each CA.

You can right-click the cert file on the client and install certificate, follow the wizard.  If the defaults don't take you can try manually selecting the store and browsing, checkmark on for 'show physical stores' and then select trusted root certification authorities.