I recently used Registry Cleaner to try to clear some space on a drive, but cannot now use my computer. Every time the computer is restarted, it just repeats the registry check, says that it is complete with an ok prompt. (I cannot use the mouse to click on 'ok', hence the only available options of Ctrl Alt Delete or switching off.)
I had a similar problem recently with a piece of software (a modem driver installer) without a Cancel button trying to run every time I switched on. I was able to stop it by pressing Ctrl-Alt-Del as soon as the software triggered, and then ending the task in Task Manager. Are you able to do that -- i.e. Ctrl-Alt-Del before Registry Cleaner says it's complete?
Then to stop it happening next time, I ran msconfig and deleted the offending software from my startup list.
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