Need help with software and features

[Benjy1985]

Hey guys. Was wondering of anyone could kindly help me at all. I've recently purchased a "refurb" and unlocked galaxy note 4 SM-N910F according to the phone. It says the current firmware is 5.0.1. I have heard that the Galaxy Note 4 supports android 6.0.1 but when I go to the software update section and press check for updates it momentarily says "registering device" then after 15 Seconds or so, it shows the message "process failed" I'm not sure if it is because it's rooted or because perhaps it was an AT&T or T-mobile phone in the USA, as it has that T-mobile chime as the ring tone. But basiliclly getting to the point I want to upgrade my phone to Android 6. If I flash with a custom rom that's based on Android 6 like cm13 would that work? And one last question the Bluetooth tethering feature seems to be disabled on my phone also. If I updated to Android 6 would this feature appear on there, as I know the phone does support it.
Many thanks for your help in advance
Ben

 

[Golfdriver97]

Welcome to the forums. The model number indicates that it's an international phone. The best of my knowledge was you should be able to root and flash a ROM to that device. I would just make sure you include your model number in any searches you do (been a long time since I rooted a Samsung).

 

[Bosbouer]

The N910F can be flashed using ODIN. Firmware can be found on the SamMobile website. Flash the country specific firmware to be on the safe side.

 

[B. Diddy]

Welcome to Android Central! You could also try using Samsung Smart Switch to see if it can check for updates specific to that phone.

 

[Bosbouer]

As to the comment on your other closed post, marshmallow works very well on the N910F.