HTC EVO 3D can see networks but will not connect

[AC Question]

Hello, I have a EVO 3D that is suddenly unable to connect to WiFi. The phone used to be on the Sprint network but now I run strictly off WiFi. When I select a visible network and enter the password 'connect' remains greyed out and unable to be selected. I have factory reset the phone, and the problem still occurs. I can still connect to networks that do not require the security key.

Thank you in advance for any help.

 

[B. Diddy]

Welcome to Android Central! Are you certain you're entering the correct password, or the correct number of keystrokes? The Connect button will remain greyed out until you've typed in the correct number of characters in the password--the password can still be wrong, but the Connect button will appear then.