To fix wi-fi problem on 4.4.2 android you have to rename Wi-fi Direct device name.
To do that you have to go:
WiFi - then 3 dots - WiFi Direct - 3 dots - Rename Device - HTC One.
Unbelievable it worked for me as well!!thank you very very very very very much !!!!!! me also register an account to thank you.
I have this phone since 4.1 and I have always connected to my home router a FritzBox 7140 from HTC desire to....to HTC ONE having always the same settings!
Upon upgrading to 4.4.2 it stopped connecting!
By applying the above setting it worked!!!!!
Thank you very much!!