The error message "Unable to initialize installer GUI" usually only happens when you're trying to "install" a program.. Which is it?
And more importantly, which operating system are you having issues with? Make and model number?
If you're having problems installing things, then there are a few possibilities..
1. Decrapifier corrupted the Windows Installer.. If you're using Windows XP or Vista, then try installing the latest Windows Installer for your machine at the link below. If you can't download on your computer, then download the file on a friend or family member's computer, then copy it to a CD or flash drive, then transfer it to the problem machine.:
http://www.microsoft.com/download/en/details.aspx?id=8483
2. Sometimes, the error you're showing can be the result of malware. If that's the case, then follow the instructions in the link below to scan your computer.
http://forums.cnet.com/7726-6132_102-5179883.html
Hope this helps and let us know more.
Grif
I ran Decrapifier and afterwards went to download a program. I then got the error message and now every download I have tried, except Opera, has failed. I already tried restoring to before it all started, but no luck. I only deleted 4 items with Decrapifier. One was a game, one was realtime player, another was BandiMPEG1, and I can't remember what the last was.

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