Modifying SCOM R2 Agent on W2K08 throws error: ‘Microsoft ESENT keys are required to install this application.’

When one runs a W2K08 server with the SCOM R2 Agent installed and want to modify that SCOM R2 Agent, like making it multi-homed, this error might be thrown:

And:

UAC (User Account Control) is the culprit here. Which is simply solved by running the specific msi command from an elevated cmd-prompt. For SCOM R2 based Agents:

Microsoft has also released a KB article about it, KB969569 which tells you what msi command to use for the SCOM and SCOM R2 Agents.