One of the lessons here is to not diddle with such cleaners. I could ask what you were trying to fix in the first place. But let's move to recovery...
In your post, you didn't tell if you tried:
1. LKGC.
Last known good config (LKGC) is a good idea. Try it.
2. SAFE MODE.
Boot to safe mode and use SYSTEM RESTORE to before the EasyCleaner.
3. Don't diddle with the machine.
4. About the software in question. NAME NAMES. What company won't honor your license?
Bob
Running a AMD 2400+ with 756 Ram and Win XP Home OS. Recently ran a program called EasyClean. Cleans reg and duplicate file etc. After running the program I rebooted to find that Windows would no longer come up. It will go to the logon screen and then shuts down. Have been unable to recover the system to where it is usable. Have some programs on there that have proprietary codes. The manfacture will not give me a new key code. Is there any way to recover any of this. Have been able to save most of the data onto another hard drive, but key codes missing and will not operate program.

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