You need to have stock recovery and no system changes for OTA to work.

---------- Post added at 08:17 AM ---------- Previous post was at 08:17 AM ----------

Easiest just to flash 4.4.4 with fast boot.
Sent from my new HTC One M8, N7, Moto X, GTab3 or S2.

Need help with poor battery life on the N5...or any device really? Lots of info in first 4 posts! >>>>
[Battery Life Help] Troubleshoot Battery Issues Here....and Tips