This morning I tried installing Microsoft Virtual Server 2005 Standard Edition for some testing and development work. But at some point the installer told me: “Error 1402: Could not open key: HKEY_LOCAL_MACHINE\Software\Classes\Msxml2.DOMDocument.4.0\CLSID. Verify that you have sufficient access to that key, or contact your support personnel.”. A little Google told me more people had the same problem, but I couldn’t find a solution (at least not on the first 2 result pages).
So I had a look at the registry. Everything seemed fine.
Since the error complains about Msxml2.DOMDocument.4.0 I figured this had something to do with MSXML 4.0, so I downloaded the installer and tried installing it. An lo’ and behold: The same error message. Then I decided it was time for drastic measures. I went into the registry to HKEY_LOCAL_MACHINE\Software\Classes and deleted every MSXML entry that ended with 4.0. Then I tried installing MSXML 4.0 again and it worked! Then I tried installing Virtual Server 2005 again and it worked!
Yet another weird problem solved…

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