Windows registry is an information bank which stores settings and options for the operating system for Microsoft Windows versions like 32-bit, 64-bit and Windows Mobile. It includes relevant data and settings for all the hardware, software your system, application of non-operating system, PC users, preferences of the computer, etc.
A registry repair software is a program that searches the registry for obsolete and redundant entries. Applications and software often create Registry keys for short-term data and pointers to other records, but never completely remove it. You can check out the best pc cleaning software at https://www.bleachbit.org/.
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On the other hand, if the folder is manually deleted by the user, Registry entries may direct to files that no longer exist. A Registry cleaner can be part of a system utility or third-party software. A registry cleaner is designed to remove items that are unused or unneeded from the Windows registry.
Some uninstallers do not totally remove all the files from the registry. These traces can interfere with how your computer works and how the system performance. The only solution to remove files that are not desired is to use a registry cleaner to scan your computer. The registry cleaner scans the registry for the unwanted files, make a list of these files and asks whether you want to delete all of them.