Fix Rundll32 / gameux problem

On Windows Vista and newer Unreal without reason may from time to time refuse to run if you don't have internet connection. Or sometimes even when you have internet connection. Instead, some stupid rundll32.exe with gameux.dll as parameter launches together with Unreal.exe, hangs Unreal.exe process and comsumes 50% CPU. When you kill rundll, it kills Unreal also. If you launch second instance of Unreal, it works, but the first instance with rundll remains.

It turns out that this useless Windows "feature" is the Game Explorer which tries to connect to Microsoft server to send/receive some information.

How to fix this?

1. Start cmd.exe as administrator.
1.1. Run command: "regsvr32 -u c:\windows\system32\gameux.dll"
1.2. On 64-bit system also run command: "regsvr32 -u c:\windows\SysWOW64\gameux.dll"
2. Open registry editor (regedit.exe).
2.1. Go to "HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\GameUX"
2.2. There will be three sub-keys: "Games", "MachineSettings" and "{something}"
2.3. Expand the "{something}" key and delete sub-keys which are for Unreal. Or just delete the entire "{something}" key.

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