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Are old Firefox keys, e.g., Firefox 1.0.6 needed in the Windows Registry, or should updates have deleted old keys?


I have old keys in my XP Windows Registry going back for eons. Leave them alone? Should any upgrade have deleted old ones? They appear in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Management\ARP Cache.

Chosen solution

You can try to delete the ARP cache.

  • netsh interface ip delete arpcache
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Chosen Solution

You can try to delete the ARP cache.

  • netsh interface ip delete arpcache

Helpful Reply

Thanks cor-el!

Your citation helped and caused additional research, as I have quite an accumulation there, and now I am finding it isn't all Firefox!

This link may help, too:


At least one computer magazine publisher quit acquiring, testing, evaluating and writing about registry software a number of years ago, because they could find no system improvement was evident after a registry product was run.

Other wise systems developers have said that the "perfect" registry cleaner probably doesn't exist; that's it a balancing act between being too lethal (and bringing the system down) or too lite (and a waste of time), therefore each of us must define how squeaky clean we wish to be.

For me it's a curiosity thing!