Garmin Edge 840 does not connect to Garmin Express

I also have had issues getting the Edge 840 to connect to Garmin Express on MacOS 15.2. since 25.24 It would never show green in GarminExpress no matter what I did. Including setting the Edge device to USB MTP Mode. (Instructions in zarmapi's post)

Environment Mac Studio running MacOS 15.2

Edge Device running 25.25

Here is what I did to finally get connected.

Completely removed Garmin Express from MacOS and did a clean install. 

Disconnected all drives from the Mac

Performed a full reset of the Edge 840( this was the nuclear option but up to this point I couldn't discover the Edge in Garmin Express not matter what mode I was in)

After running thru initial sets on the Edge I reconnected using USB MTP mode, 

I still could not discover the device.

At this point I restarted the Edge and reconnected the cable, it was now showing connected to a PC in the Edge screen and Garmin Express finally discovered it!

Unfortunately to do anything like map updates I had to disconnect, reset the device to USB MTP mode and now Garmin Express sees the connection and I can perform sync, update maps, install IQ apps etc. 

I don't know if my device software state was funky, but the full reset was the only new step performed to get connected, every other step was tried multiple times with multiple reboots of the computer and device thrown in.

The entire process since switching to USB MTP mode is a terrible experience and I feel Garmin has let its OS users down with this switch. 

I don't advocate the full reset to fix this! I was just the willing sucker that wanted to see if it would help with the problem. :) I now have the fun of resetting the device back to how I like it. 

Thanks for the insight Pai2Uk. As mine is still new I had tried this strategy as well though that was before I had known about the USB MTP trick.  I'm loathe to go through all that again without knowing the end result will be different for sure. I maintain skepticism because I've trying all sorts of things to get this to work too and after uninstalls, reboots, USB MTP attempts and I'm not sure what other unobserved changes occurred, maybe it was the reset but I definitely didn't see it appearing directly after but it did reappear for me in garmin once, briefly. The appearance was long enough to see the green light on the main screen.  

Unfortunately the *only* thing I want is to drop files from my old garmin onto the NewFiles folder in the new garmin and I can't seem to make it work, showing up in Garmin Express only is insufficient, not really even necessary for me.  Thankfully my son is home with his windows laptop so I'm hopeful I can achieve my objective with his machine. 

Feels worse than a let down to Mac users, frankly. This level of negligence is new.

I had to help a colleague with a similar problem on a Garmin edge 1040, and I had to do the nuclear solution. I think the update process doesn't work quite right. Thanks to Garmin for making our lives so easy

I got a Firmware update yesterday 25.25 or somerhing). Garmin Express Sees the Edge now, but map Updates still don‘t work.

To get map updates you need to be in USB MTP mode, make sure you are in that mode, after that my maps updates worked.

Not working for me even after updating to 25.25 and following the instructions from zarmapi to enable MTP mode

26.07 should be out, I will test it tomorrow

skorbuly are you using a PC or a Mac?

Come on: the picture clearly shows a Mac!