Hi ganesan, it's good to see you
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again!
I agree with each of our member-friends whom have already given you, in my opinion, the very best & safest advice with how to approach registry cleaning.
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Whether you'll choose to clean (or not) CCleaner is truly a favorite software among many more than our very own brethren here on MT.
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In fact, before I found this thread I'd run both a system cleaning, & a
wipe of all
free space remnants (found under "Tools") for an external flash drive that I'd formatted (completely erased). I did not clean the registry, but have once or twice before, and only with CCleaner!
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All I shall add is recommending their portable version which can become a part of the practice of keeping one's computer's system lighter by keeping certain apps separate from your system. I do this mainly with browsers, but also with CCleaner!
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