Updated:  Added an image for the registry entry and clarified some details. 

As a follow up to my last post about overriding the hard block for Windows Server 2008 in the Zune 3.0 setup launcher (http://blogs.msdn.com/dzazzo/archive/2008/09/16/installing-zune-3-0-on-windows-server-2008.aspx), I wanted to make sure I reached out and provided instructions on how to upgrade to Zune 3.1 from Zune 3.0. 

If you've gone ahead and tried this, you'll realize that Zune 3.1 also has the hard block for Windows Server 2008... AND, you can't unintall Zune 3.0 because the item in Programs and Features executes ZuneSetup.exe, which ... has the hard block.  So, what to do?

The trick to "upgrade" to Zune 3.1 is to uninstall Zune 3.0 using a workaround, then install Zune 3.1 using the same workaround I previously blogged about.

Uninstalling Zune 3.0

To uninstall Zune 3.0, you won't be able to use Programs and Features.  The Remove button there executes ZuneSetup, which we know won't work.  To find the "real" uninstall string, we need to go digging into the registry. 

(Warning: Wrong action on registry may potentially damage your system. Please make sure to back up your registry before taking any action).

Open up Registry Editor, and navigate to the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall key.  Search for a GUID entry for Zune.  (A GUID looks a lot like {FF70513F-E3A7-402F-84FB-B7810A064BE2}.)  See the following picture for an example of what I'm talking about:

(If your UninstallString includes ZuneSetup.exe, then you've probably looked at the "Zune" registry key, not a  GUID registry key.  Search above for another Zune key -- hint:  compare the DisplayName value to "Zune") 

Once you find a GUID entry for Zune, look at the UninstallString.  It should look like:

MsiExec.exe /X{FF70513F-E3A7-402F-84FB-B7810A064BE2}.

Copy that command to your clipboard, drop down to a command prompt, and run it.  You should see Zune 3.0 start to uninstall itself from your machine.  Once it's complete, you can then turn around and use the previous workaround to install the Zune 3.1 software on your Server 2008 system.

I'll also update the existing post, but I would recommend keeping the extracted Zune 3.1 binaries around - if you kept the Zune 3.0 binaries, then you would be able to easily run "MsiExec.exe /X Zune-x64.msi" instead of digging around for a GUID in the registry.

And, as always:

This absolutely not supported or endorsed by Microsoft.  If you use this workaround, get Zune installed on Windows Server 2008, and then it doesn't work, make sure you can repro your problem on Windows Vista before calling for support.

Also, don't install Zune on a production server.  That should be an obvious one. (Note that this doesn't apply to Zune specifically - don't install any media playback or anything unnecessary on a server system.)

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