My bet is it's not configured to get those files to the server. Or someone installed a firewall. But the issue is VERY well discussed. Here's a start.
Bob
-> https://www.google.com/search?as_q=localhost+cannot+find+PHP+files+xampp
Or so I assume. That's what it was telling me, now it just freezes Firefox and Chrome.
I had XAMPP installed for a time after switching from WAMP. After some weeks I decided I liked WAMP better for it's homepage, so I uninstalled XAMPP, and reinstalled WAMP.
It would not read my PHP files. Firefox and Chrome both stated that it could not find the file. So after varied attempts I uninstalled WAMP, and installed XAMPP again.
Now typing a localhost path into the address bar that I know is valid freezes Firefox and Chrome.
My registry was cleaned between steps.
Any advice is very much appreciated!
Regards;
*

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