Here’s a new Knowledge Base article we published today. This one tells you how to update or add the product key in System Center 2012 Operations Manager:
After you installing System Center 2012 Operations Manager, you may look at
Help -> About
and see (Eval) after the Version info.This article describes how to add a Product Key to the Eval edition of System Center Operations Manager 2012.
To set the product key, use the Set-SCOMLicense cmdlet in PowerShell. To use the Set-SCOMLicense cmdlet you need to use elevated permissions. (Run as Administrator).
1. Open PowerShell as and Administrator
2. Load the OperationsManager Module (import-module operationsmanager)
3. Connect to your ManagementGroup (New-SCOMManagementGroupConnection)
4. Use Set-SCOMLicense “yourlicensekey“
5. To check if changes were executed run Get-SCOMManagementGroup | ft skuforlicense, version, timeofexpiration –a