Is my HTC One M8 locked to AT&T or unlocked?

[eak1570]

I just bought HTC one M8 from eBay and the seller said unlocked and the box is seal but after I open the box and turn on the phone.. The phone run AT&T boot and a lot of AT&T software... I don't know how is possible because the phone doesn't have at&t logo on the back..

The phone currently run on 4.4.2 and said up to date..

1. Can I flash the lolipop or above rom? If yes please give me an advice..
2. Why the phone run at&t software even no brand and unlocked?
3. What is the latest update for AT&T M8?

Thanks.

 

[Rukbat]

1. Can I flash the lolipop or above rom? If yes please give me an advice..

Yes - nothing to do with being unlocked. See AT&T HTC One (M8) for ROMs and flashing help. If it's not actually an AT&T phone (look on the lower back - the model number is in a tiny font), see HTC One (M8)

2. Why the phone run at&t software even no brand and unlocked?

It was flashed with an AT&T ROM.

3. What is the latest update for AT&T M8?

See #1.