HTC One M9 - Manual (Page 136)

HTC One M9 not responding?
If HTC One M9 does not respond when you touch the screen or press the buttons, you can
still restart it.
Press and hold the POWER and VOLUME UP buttons for at least 10 seconds. HTC One M9
then restarts.
Resetting HTC One M9 (Hard reset)
If HTC One M9 has a persistent problem that cannot be solved, you can perform a factory reset (also
called a hard reset or master reset). A factory reset reverts the phone back to its initial state — the
state before you turned on the phone for the first time.
Factory reset will remove all data on your phone storage, including apps you've downloaded and
installed, your accounts, your files, as well as system and app data and settings. Be sure to back up
any data and files you want to keep before you do a factory reset.
A factory reset may not permanently erase all data from your phone, including personal
information.
Performing a factory reset from settings
1. From the Home screen, tap > Settings > Backup & reset.
2. Tap Reset phone.
To also delete media and other data from your storage card, select Erase SD card.
3. Tap OK.
136 Sync, backup, and reset