It's been 3 or 4 years since this came up: My Phantom 4 Pro link button doesn't work. RC and aircraft versions corrallate, all batteries charged. Plus the firmware update hangs at 24%, and the error message indicated an unstable connection BUT EVERYTHIGNG IS HARDWIRED TO THE INTERNET.
Help?

Hi, sorry to read about the issue, please try to use DJI Assistant 2 on the computer to refresh the latest firmware (https://www.dji.com/uk/downloads ... t-dji-2-for-phantom) and relink the drone and controller.
If the issue persists, you may need to send the drone back to our service center for further diagnosis.

DJI Susan Posted at 6-17 19:32
Hi, sorry to read about the issue, please try to use DJI Assistant 2 on the computer to refresh the latest firmware (https://www.dji.com/uk/downloads/softwares/assistant-dji-2-for-phantom) and relink the drone and controller.
If the issue persists, you may need to send the drone back to our service center for further diagnosis.

DJI Assistant flakes out at 24% upgrade and gives me an "unstable connection" error message. The link button doesn't function and my Phantom 4 Pro (for which I paid an arm and a leg) won't link with my RC... Why can't you figure out a way for the RC to connect with a USB to the PC, and the P4P connect via USB to the RC, and then everyone gets upgraded with the same version at the same time. This Mickey procedure is costing me time and money!!!

PADSLLC Posted at 6-19 16:32
DJI Assistant flakes out at 24% upgrade and gives me an "unstable connection" error message. The link button doesn't function and my Phantom 4 Pro (for which I paid an arm and a leg) won't link with my RC... Why can't you figure out a way for the RC to connect with a USB to the PC, and the P4P connect via USB to the RC, and then everyone gets upgraded with the same version at the same time. This Mickey procedure is costing me time and money!!!

Sorry that the controller does not support connecting the computer for firmware updates.
If it is possible, you may try with a different computer to refresh the firmware for the drone,  the issue relates to the controller or it persists after the firmware update, I'd suggest sending the drone and controller back for further diagnosis.
Please fill out the online repair request on our official web and send it back. Here is the link: https://repair.dji.com/repair/index
We will do our best to help this out.