Problem:
==========

While trying to install agents in SCOM SP1 setup we were getting error as “SPN error: event id 21001 and 20057 with source OPS mgr connector”

Cause:
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Duplicate SPN’s was causing this issue.

Resolution:
=========

We manually deleted the duplicate SPN’s.

You can refer to the Method 1 listed in the following KB article:
http://support.microsoft.com/kb/321044

Method 1: Use the LDP support tool

Note If you do not have the Windows 2000 support tools installed, install them from the Windows 2000 CD-ROM before you continue. The Setup executable file for the support tools is located on the CD-ROM in the Support\Tools folder. The installation does not require that you restart the computer. However, you may have to restart the computer to update the environment variables.
  1. Click Start, click Run, type LDP, and then click OK.
  2. Click Connection, and then click Connect.
  3. Leave the default settings, and then click OK.
    Note If you do not receive the expected result, try another search by using the Global Catalog Port (3268) instead of the default setting (389).
  4. Click Connection, and then click Bind.
  5. Leave the default settings, and then click OK.
  6. Click View, and then click Tree.
  7. In the Tree View dialog box, type DC=YourDomain,DC=com in the BaseDN box, where YourDomain is your domain.
  8. Click Browse, and then click Search.
  9. In the Search dialog box, type DC=YourDomain,DC=com in the BaseDN box.
  10. In the Search dialog box, type (serviceprincipalname=HOST/mycomputer.mydomain.com) in the Filter box. If the service principal name that is referred to in the error in the System log differs from this example, type the service principal name to which the error refers.
    Note If you do not receive the expected result, try searching for " HOST/" as opposed to searching only for the exact SPN in the event ID.
  11. Under Scope, click Subtree.
  12. Click Run.