Once you have a Windows Registry backup, you need to know how to restore it. Malware and viruses of all types regularly attack and modify the registry and will require immediate attention.

If your computer is suddenly turned off, or crashes, or dies for another reason, it could cause an issue in the future-but this is unlikely. Each time your computer shuts down, a copy of the registry is saved to the system memory.

System Shutdown Errors: Unlikely to cause issues.

Similar to duplicate keys, the registry fragments when software is uninstalled, upgraded, or updated.

Registry fix software will advise that your software will be 'confused' by the duplicate entries, slowing your machine, but in reality, this is unlikely. Duplicate keys are made when you reinstall, upgrade, or update software on your machine, including the operating system.

Many registry fix software will proclaim these are an immediate issue, but in reality, they amount to nothing more than a few kilobytes of data in your machine. Orphaned entries occur when you uninstall programs, and small fragments of registry entries are left behind. There are several common causes of registry errors, some worth worrying about, others not:

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