Originally posted by arleas in GameSpot forum:

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For those trying to uninstall the DVD version (or any version that's having problems)

The DVD version has trouble with uninstalling.... as far as I know, this problem exists only for the DVD version....

What you need to do is this:
1) get Spybot S&D if you don't already have it.
2) read the helpfile/instructions to find out how to open it in "advanced mode" (if you can't read those instructions then these aren't going to do you any good)
3) open Spybot S&D and select "tools" and then select "uninstall info"
4) from there you'll see a list of everything that is currently installed. Find the entry for UT2004 and delete it...

This does NOT remove the files... this only removes the uninstall entry because it's buggy anyway...

5) go to your UT2004 folder and delete it (the easiest part)
6) open up regedit (START > Run > regedit)
7) delete the following registry entries (or use a registry cleaner to remove the stuff that doesn't apply anymore)
HKEY_CLASSES_ROOT\unreal
HKEY_CLASSES_ROOT\ut2004
HKEY_CLASSES_ROOT\UT2004.Link
HKEY_CLASSES_ROOT\UT2004.Map
HKEY_CLASSES_ROOT\UT2004.Module
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\unreal
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\ut2004
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\UT2004.Link
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\UT2004.Map
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\UT2004.Module
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\UT2004
HKEY_LOCAL_MACHINE\SOFTWARE\Unreal Technology

Of course if there are more entries, they're not as easy to find... which is why a registry cleaner would probably do you the most good... and I've only listed the top of the tree that needs to be deleted, so if there are other things beneath it, obviously they need to go too...

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