Unable to logon to Lync Server Control Panel

You may recieve an error when logging in to the Lync Server Control Panel for the first time from a computer or even the Lync server itself.

When you launch the Lync Server Control Panel Silverlight application from the Start menu or open https://lyncserver.domain.com/cscp in Internet Explorer, you must enter a username and password for an account that is a member of the CSAdministrator group in Active Directory.  You may then receive the following IIS error:
Unauthorized: Authorization failed.
The application cannot verify your credentials.
Verify your logon credentials and contact your support team.
This happens when the https://lyncserver.domain.com/cscp website is not in the computer’s Trusted Sites zone.  Here’s how to fix it:
  • Launch Internet Explorer
  • Double-click the Security Options zone information at the bottom of the IE window:
  • This will open the Internet Security Properties window.  Click Trusted Sites and then the Sites button.
  • Click Add and Close to add the https://lyncserver.domain.com site to the Trusted Sites zone.

Now you will be able to access the Lync Server Control Panel from both Internet Explorer and the Silverlight application on that computer.