My M300 is. grounded, an avionics error 0x16100091 preventing take off. It happened all of a sudden, after one successful flight and without powering off the aircraft the error wouldn't allow me to take off again.
So far no response from DJI support, this is what I've tried so far:
Installed DJI Pilot PE - did not resolve the issue.
Calibrated vision sensors  - did not resolve the issue.
Downgraded aircraft and controller firmware - did not resolve the issue.
Upgraded firmware again - did not resolve the issue.

Then I got another message telling me of incompatible firmware, but didn't say what component it was. I activated the slider on screen to update and all I got was some Chinese text with an upgrade button and nothing appeared to happen. I waited 30 minutes with a busy symbol on the screen and eventually manuallly shut the controller down and re-started it. Everything showed normal except the "Unable take off" message, all other conditions were good. Ultimately still can't fly.

How many others are having this issue, I know of one other thread that hasn't progressed to any answers yet (Other forum post).

https://www.dropbox.com/s/g18wubchhcq3hhd/1114-134947.mp4?dl=0

UPDATE: A solution came through from DJI Tech via another user in this thread ->> https://forum.dji.com/thread-228118-1-1.html
In short, I disabled the pilot app, downloaded the Pilot APK and presto it's working again.

Hi there, sorry for the inconvenience caused. This issue has been reported to our engineers, our team is working hard on it at present. By the way, I've managed to get your ticket number via your forum account, if there is any update, we'll keep you updated and reply to your email. Thanks for your patience.

DJI Natalia Posted at 2020-11-14 01:59
Hi there, sorry for the inconvenience caused. This issue has been reported to our engineers, our team is working hard on it at present. By the way, I've managed to get your ticket number via your forum account, if there is any update, we'll keep you updated and reply to your email. Thanks for your patience.

I have a mavic 2 enterprise advance with the same problem. If i start the props before a gps lock and let them idle til a gps lock I can take off. Dont know if its as safe but what can you do.I think it with geo fencing.

mechanical1 Posted at 6-30 17:42
I have a mavic 2 enterprise advance with the same problem. If i start the props before a gps lock and let them idle til a gps lock I can take off. Dont know if its as safe but what can you do.I think it with geo fencing.

Hi, there. We are sorry for the problem caused. We will confirm your problem to the relevant team and keep you updated. Please don't worry.

DJI Natalia Posted at 7-1 01:03
Hi, there. We are sorry for the problem caused. We will confirm your problem to the relevant team and keep you updated. Please don't worry.

Update: Hi, there. We have confirmed with the engineer and the following information is for your reference: Different versions have regional restrictions. When the GPS search of the aircraft is normal, the aircraft will automatically identify where it is, and then evaluate whether it can fly in this place according to its own version restrictions. If the GPS search is not completed, it will take off first, and there will be no more restrictions. However, once the drone lands, it can not take off again.

DJI Natalia Posted at 7-1 03:58
Update: Hi, there. We have confirmed with the engineer and the following information is for your reference: Different versions have regional restrictions. When the GPS search of the aircraft is normal, the aircraft will automatically identify where it is, and then evaluate whether it can fly in this place according to its own version restrictions. If the GPS search is not completed, it will take off first, and there will be no more restrictions. However, once the drone lands, it can not take off again.

Hi, I bought the Mavic 2 enterprise advance from Sweden. How can I update my gps for the US region? There must be a way to change ownership to a new country.I would like to use the drone to its full potential and did not understand the different countries different gps software. If I travel to another country how to update for that country?  I am just getting started in inspections and mapping and would like this drone  to work. Thanks for any help.

mechanical1 Posted at 7-2 21:44
Hi, I bought the Mavic 2 enterprise advance from Sweden. How can I update my gps for the US region? There must be a way to change ownership to a new country.I would like to use the drone to its full potential and did not understand the different countries different gps software. If I travel to another country how to update for that country?  I am just getting started in inspections and mapping and would like this drone  to work. Thanks for any help.

Could you please tell us what version of your Mavic 2 Enterprise Advanced? Please note that Mavic 2 Enterprise Advanced can only be used in the country/region of the corresponding version. No cross-region usage is supported. If it's a North American version, it can only be used in the United States, Canada, and Puerto Rico, and cannot be used in other countries/regions, and vice versa.

DJI Mindy Posted at 7-3 00:00
Could you please tell us what version of your Mavic 2 Enterprise Advanced? Please note that Mavic 2 Enterprise Advanced can only be used in the country/region of the corresponding version. No cross-region usage is supported. If it's a North American version, it can only be used in the United States, Canada, and Puerto Rico, and cannot be used in other countries/regions, and vice versa.

Hi,on the remote my aircraft version# is 1.00.0520 and the app is 2.5.1.10 . On the drone it has a FCC # and does not say what country it is for.Do you have a link that will show how to tell what country a drone is made for?
Thanks

mechanical1 Posted at 7-3 11:47
Hi,on the remote my aircraft version# is 1.00.0520 and the app is 2.5.1.10 . On the drone it has a FCC # and does not say what country it is for.Do you have a link that will show how to tell what country a drone is made for?
Thanks

Thanks for the update. We are sorry that we don't have any links like that. Could you please send us your SN via PM? Then we will confirm and reply to you as soon as possible.