Using registry cleaning software has always been a "risky business", whatever the quality of the used program. If you let the software take automatic decisions about what elements of the registry should be eliminated or modified, you are certainly exposed to some annoyances, to say the least.
As far as PC TimeWatch is concerned, the information related to the license key might be corrupted by such registry cleaning operations. If PC TimeWatch refuses to start after a registry cleanup, you'll have to enter your key again in order to re-activate the software. You don't need to request a new key unless you lost it. Your license key is permanent and can be re-used in this case.
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