If you need to recreate the CEM web site use the following steps:

1. Stop the Altiris Service

2. Remove the site from IIS

3. Delete the HKLM\Software\Altiris\NS Agent Site.  

4. Go to the HKLM\Software\Altiris

5. From the above location in step 4 delete the AgentWebSite value

6.  Delete from "HKLM\Software\Altiris the tsSecondaryWebSite value. 

7. Run an 'iisreset' and then Restart the Altiris Service

8. Go to the Settings>Notification Server>Cloud-enabled management>Setup>Cloud Enabled Management Agent IIS Settings

9.  Check the box to add an IIS web site and make sure you use the appropriate certificate and click save