Use a program like CCleaner (either the free or Pro version) and use that to uninstall the ATI Install Manager (you can do the same through Add/Remove Program, I just find that CCleaner does a better job of uninstalling). After you've uninstalled it, do not restart your system yet, use the "Registery Fix" tool in CCleaner to remove any dead ATI registery keys.
Reboot into safe mode.
Once in Safe Mode, use a program like Drive Sweeper (you can download it
here to remove any left over files). After this is done, restart your computer again and boot into safe mode once more and install the ATI drivers. When installing the drivers, make sure that you select "Custom" install and check CCC to be installed and then follow the rest of the process as instructed on screen.
Having said that, there is a better solution. Follow the instructions to uninstall and reinstall your ATI drivers, however, at the point where you select to install CCC when doing the custom installation, do not check CCC. Just check the WDM driver (and HDMI if you need to) and that's it. Next, go
here to download ATI Tray Tools to replace CCC. ATI Tray Tools is a far better program than CCC with a vastly smaller resource footprint that is far more powerful tool than CCC is.
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