So I've looked up the forums and encountered the 0x20106 Error whenever I'm trying to update to V.01.04.0000
A recent thread was opened and was answered by an admin, DJI Thor.

I followed the instructions after requesting the beta access for my account.The drone was able to succesfully downgrade to beta v. 1.03.0813 through the DJI Assistant 2 application.
The current problem now shifts to my RC not detecting the drone after the update.


Situation:
-Drone at beta v. 1.03.0813
-RC at v. 01.04.0000 now downgraded to v 1.03.1000
-No SD card attached during upgrade/downgrade


So here's what I've tried out after several troubleshooting:

• RC on v. 01.04.0000 will not detect the Drone on beta v. 1.03.0813
• RC on v 1.03.1000 will detect the Drone on beta v. 1.03.0813
• Downgrading the RC to beta v. 1.03.0813 with the DJIA2 keeps failing at 15%.
  
• 'Restore Factory Default' would keep failing before starting.
• Downgrading the RC to v 1.03.1000. Success.
• Upgrading the drone to v 1.03.1000 or above through DJIA2 while RC is connected or not will provide the same error 0x20106 again.
  

Pressing once or press+holding the Record button when updating the drone shows no significant change in situation.
A 'Check App' Error pops up on the RC while connected to the drone that's being updated.

So with what I've tried, I'm at a loss at what to do.
Please do inform me if I made some mistake in taking the necessary steps.

TIA

I forgot to ask these:
-do I need to press the Record button when upgrading through the app.
-is the SD card a necessary requirement when updating? I don't have it now but I can just get a new one.
- do I need the phone to be connected to the RC and have both the RC and the drone update through the DJI app instead of the DJI Assistant 2 when updating?

This beta firmware is doing nothing with the RC. Please refer to the steps below to upgrade the drone again.
1. Log into your DJI account.
2.Upgrade the firmwareV1.3.8.13
3. Once it's done, please press the "Record" button and make sure it's recording, then start to upgrade firmware to the latest one, it will be working.

DJI Diana Posted at 2017-11-17 02:16
This beta firmware is doing nothing with the RC. Please refer to the steps below to upgrade the drone again.
1. Log into your DJI account.
2.Upgrade the firmwareV1.3.8.13

Oh ok. So to clarify, I need to pair my RC with the drone right?
The problem is that the RC isn't connecting with the drone even if I followed these steps?

k2m2 Posted at 2017-11-17 02:19
Oh ok. So to clarify, I need to pair my RC with the drone right?
The problem is that the RC isn't connecting with the drone even if I followed these steps?

Got your PM, you don't need to use an SD card to upgrade, but you need to make sure that the drone and RC are linked normally. Please try if you can control the gimbal by the RC gimbal wheel. If you are not able to control it, please try to relink the RC and AC and update again.

SOLVED!!!!After trying everythingggggggggg....

I Saw this on someone's else post and i can verify this worked for me.
You have to use an IPHONE. I used IPHONE X, the other guy used IPHONE7 PLUS.  (6 will not work)
You just update using the DJI GO 4. (note: on iphone DJI GO and DJI GO4 are different)

whenever the percentage seems stuck, or slowed - PRESS the video shoot button - a lot of clicks untill it wil continue. (it takes time. if its not failing - its working)
this is how you get to 100% and update completes.
if this wont work for the first time, try again!  i succeded on 3rd try.

Enjoy