I had four clean Windows 2008 R2 installed servers all in a row fail when installing Forefront Unified Access Gateway with the same error:
Log Name: Application
Source: MsiInstaller
Date: 9/29/2011 1:10:10 PM
Event ID: 11406
Task Category: None
Level: Error
Keywords: Classic
User: DOMAIN\#ServiceAccount
Computer: localcomputername
Description:
Product: Microsoft Forefront Threat Management Gateway — Error 1406.Could not write value InstalledBy to key \SOFTWARE\Microsoft\Updates\Microsoft Forefront Threat Management Gateway\7.0.8108\Service Pack 1. System error . Verify that you have sufficient access to that key, or contact your support personnel.
There was nothing out there helping me. I finally found in Microsoft KB969865 saying: “When you run .NET Framework 3.5 SP1 setup with a user account whose name begins with a ‘#’ character, the installation will fail.” and then it gives the error, which is the exact same as the one I got. In the cause section, it explains that the install tries to write a registry value with the “InstalledBy” username. But the ‘#’ character just happens to be a special prefix character in registry values.
So I tried it again with a different account and the install finishes with no problems at all.