I got this issue after ugrade firmware of M600 and LightBridge to latest version. Now, My Drone can not take off. Is there any solution to fix it? My system info is shown on the image below

Did you unlock it from DJI Assistant before unplugging it?

Yesterday I gave dji matrice 600 pro to the service with exactly the same problem. Service told me that this problem only occurs when you connect the android device. Before that, I checked matrice on three android devices and got the same error. Unfortunately I do not have an IOS device and now my drone can not fly.  There is no "unlock" button in "DJI Assistant". I tried to install dji go 4, log into the account, delete and install dji go, as advised in the neighboring topics. It does not help. downgrade firmvare also can not be done.  what should I do? buy a new iphone or ipad?  

Sorry for the inconvenience first. Could you export the flight logs for further analysis? You can connect with DJI Assistant 2: Flight logs>Entering SD Read Mode. Appreciate your time and cooperation.

Pazuzu Posted at 2017-11-15 08:54
Yesterday I gave dji matrice 600 pro to the service with exactly the same problem. Service told me that this problem only occurs when you connect the android device. Before that, I checked matrice on three android devices and got the same error. Unfortunately I do not have an IOS device and now my drone can not fly.  There is no "unlock" button in "DJI Assistant". I tried to install dji go 4, log into the account, delete and install dji go, as advised in the neighboring topics. It does not help. downgrade firmvare also can not be done.  what should I do? buy a new iphone or ipad?  [view_image] [view_image] [view_image]

Pazuzu, please refer my reply in 4# and offer more data for analysis, thank you so much!

DJI Susan Posted at 2017-11-17 03:39
Pazuzu, please refer my reply in 4# and offer more data for analysis, thank you so much!

I sent a link to download the log files in a private message

Pazuzu Posted at 2017-11-17 07:45
I sent a link to download the log files in a private message

Received with thanks! Also, please also copy the whole LOG file of APP from here: /sdcard/DJI/dji.go.v4.debug/LOG/  All info will be forwarded to the engineers for further review.

DJI Susan Posted at 2017-11-17 18:08
Received with thanks! Also, please also copy the whole LOG file of APP from here: /sdcard/DJI/dji.go.v4.debug/LOG/  All info will be forwarded to the engineers for further review.

I found "/DJI/dji.go.v4/LOG" and "/DJI/dji.pilot/LOG"
Send its in a private message

Pazuzu Posted at 2017-11-18 05:44
I found "/DJI/dji.go.v4/LOG" and "/DJI/dji.pilot/LOG"
Send its in a private message

Thank you so much. I have transferred to our engineers, and will keep follow up and update the status here.  

I had exactly the same problem that I fixed by using an iPad. VERY disappointed that it couldn't be done with the CrystalSky monitor, which after all is a DJI device.

I also unlocked the Drone via ipad, but the problem IS NOT SOLVED, it is unknown at what point and why it can be blocked again. Under the law of meanness, this will happen at the most inopportune moment and I can again lose money and reputation.

Pazuzu Posted at 2017-11-21 00:55
I also unlocked the Drone via ipad, but the problem IS NOT SOLVED, it is unknown at what point and why it can be blocked again. Under the law of meanness, this will happen at the most inopportune moment and I can again lose money and reputation.

Anyway, it's nice to hear that it has been unlocked successfully. Could you help us to locate the exact issue of Android APP? I'll PM you for further follow-up. Appreciate your time.

DJI Susan Posted at 2017-11-21 23:30
Anyway, it's nice to hear that it has been unlocked successfully. Could you help us to locate the exact issue of Android APP? I'll PM you for further follow-up. Appreciate your time.

Now can't reproduce the bug. The above screenshots show that displayed the error "Cannot take off". In the messages menu has been shown "Aircraft is force locked". On the drone, regardless of action is always lit solid red signal

Pazuzu Posted at 2017-11-24 01:30
Now can't reproduce the bug. The above screenshots show that displayed the error "Cannot take off". In the messages menu has been shown "Aircraft is force locked". On the drone, regardless of action is always lit solid red signal

Sorry, I did not immediately see a private message. When I return from a business trip, I will help you with the receipt of data from app.

Pazuzu Posted at 2017-11-24 07:45
Sorry, I did not immediately see a private message. When I return from a business trip, I will help you with the receipt of data from app.

Thanks so much! We appreciate your time and update. Have a nice weekend!

fans3b40a30a Posted at 2017-11-20 09:32
I had exactly the same problem that I fixed by using an iPad. VERY disappointed that it couldn't be done with the CrystalSky monitor, which after all is a DJI device.

Hello ..please tell me how to fix aircraft force locked..i do hv m 200 and it show that mesge..how to use i pad to unlock