[Chruptak]

My phone developed a really strange problem with wifi. It connects to wifi networks but can not access the internet. The connection seems OK, the phone gets IP address but it can only ping the router! Any other ping returns "destination unreachable" error.
And the really puzzling thing is that this problem does not exist on unprotected wifi networks. Eh.
I have checked on several protected wifi nets, none worked, so the problem must be with the phone itself.
So far I have tried the Wifi fixer app, but it could not fix this for me.
Phone is HTC One S, Android 4.1.1

[RedNations]

Does your WI-FI work on your computer or another device?

[Chruptak]

Oh yes, the wifi itself is fine. Other devices work correctly.

[Chruptak]

Fixed! I used 'FXR Wifi fix' app and it repaired whatever was wrong.