Change Mobile / Wi-Fi Hotspot Password - HTC One® M9
From a Home screen, navigate: Apps icon > Settings >Mobile Hotspot & Tethering.
If Settings is unavailable, tap the Dropdown menu (located in the upper-left) then select Alphabetical. If still unavailable, refer to Manage App Icons.
Tap Mobile Hotspot then tap OK if prompted.
Tap the Password field then enter the preferred password.
If the field is greyed out, tap the switch to turn off Mobile Hotspot.
Password must be at least 8 characters.
The new password must be entered on the connecting device.