Registry key in question

CCleaner for Windows
1

Hi

I have the following registry key reported as unused file extension:

HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.pf

A moment before that ,I uninstalled Google Earth, does it have anything to do with this ?

If it is some thing else, what is it?

Thanks

2

Could be prefetch files .

3
Could be prefetch files .

Is it ok then to delete?

4

That is your decision really :)

Make a backup of anything you delete when you are unsure.

5

It's totally safe to delete it. Shortly; it's just a file extension that has not been registered to open with any application.