I have tried disabling all device administrators and even deleting my Exchange account but that did not work. I am unable to clear credentials - there is nothing listed under user credentials anyways.
HTC said I could try formatting the SD card or a factory reset but I want to hear any other inputs first.
After the update to Sense 6, my Exchange account (for my university's e-mail) asked me about changing my password and then went on to try and encrypt my SD card. The files are fine (I can use Airdroid or USB) but I can't unencrypt. Many of the unlock screen options are also disabled - I cannot use pattern unlock or have no unlock, but I can use a PIN or password.