I use a long (63-character) WPA2 password. After I connect to wifi with the phone for the first time, it remembers it and reconnects as expected whenever the AP comes in range. However, after connecting to a free open Wifi AP, the phone will no longer remember the 63-character WPA2 password.
However, it *will* remember a WPA2 password if it's 45 characters or fewer. But 46 or more characters will not be remembered. Multiple Factory Resets did not clear this problem...the phone was stuck in this mode.
This happened with our first phone (right after visiting a local tire shop and using their open Wifi) and I thought it was a fluke. So we got Verizon to get us a new phone. That phone worked fine for a few weeks, until we made the mistake of connecting to an open wifi network at Panera Bread. After that, it no longer would connect to our home network, unless I lowered the WPA2 password length to fewer than 46 characters.
I can't imagine I'm the only one with this problem if it's a reliable bug, so perhaps it has something to do with our AP, or my use of MAC authentication, but I'm truly at a loss. Has anyone out there seen this, or gone through this combination of steps and still emerged with an HTC One that remembers very long WPA2 passwords?