since i bought my htc ONE that it hasn't updated OTA anytimes. i often check software update, but it inform to me no available update. so i have to update it by PC or zip file.
my ONE is unlocked by code when i bought, because i am living in Viet Nam.
As has already been said. You can only get OTA updates for an ATT phone over the ATT network. It will not work over other networks since they do not supply the update in the first place. The update comes from ATT.
Furthermore it would need to be stock even if you wanted to get an OTA here in the US. With it being unlocked it would still not receive updates.
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