Firmware 24.21 file for downgrade

Once the device is using MTP for data transfer as introduced by software 25.24 it is not possible anymore to downgrade the software version - at least until now nobody, nor Garmin itself, has described a working solution.
The file structure of the update files changed from GUPDATE.GCD to GUPDATE.GSP. If you are on 25.24 and place an earlier version file GUPDATE.GCD in the folder ..\Garmin on the device, nothing happens after restart and the .GCD file is removed. NOTE! This is not my own experience and my strong advice is not to fiddle with this risking to end with a bricked device.

Thanks for the info. Guess I'm stuck with 25.24 and MTP then...
Didn't know that FW already included MTP. This was not mentioned in the release notes for the Explore 2!
I was set to avoid the update with MTP... this is really disappointing.

Did some further reading and seems this important detail was only mentioned in the release notes for the 1040 etc.
I found mention of similar issues on the 1040 as mine. Seems deleting the maps, doing a factory reset and then re-adding maps and IQ apps fixes the issues.

So I'll have to try that.

I did also have custom map themes. Will I still be able to (re-)deploy these now with MTP?

I'll try sometime this week and report back.

Custom map themes are a matter of copying .ktmf files to the folder ..\Garmin\MAPTHEMES, so I don't expect problems with that. IQ apps are installed via Garmin Express and as long as GE recognizes the EE2 when connected via USB this will work normally.

Agree fully with you that Garmin should have communicated better about the ins and outs of introducing MTP for the EE2. In the release notes of firmware Public Beta 25.19 it was mentioned, but without details. People who are not on the beta program will have missed it.

Another negative experience after introducing MTP is that the boot time after power-on has increased significantly and file transfer to and from the device is much, much slower.

I thought Garmin can't sink deeper, but it happened. Good job

I am still on 21.18 and hopefully i will be as long as possible.

Don't you know if 24.56 is MTP?

Express showed me this version to update today.

In my archive I found change notes for version 24.54 (not 24.56!). 24.54 was the 'in between' version that converted the file system to MTP. I assume that version 24.56 will do the same. Next updates are distributed as .GSP files.
If you want to avoid this update you'll have to delete the (.GCD?) update file every time the device was synched using USB connected Garmin Express. The behavior of GE mobile or GC mobile I don't know, so be alert!

I dont know if want to avoid it, therefore iam asked. Iam reading that 25.xx is problematic and i have to factory reset it to resolve issues.. i want to do that 

The update is not instaling.. it only promted me to update, but i canceled it

I'm on 25.25 and have no issues at all. Routing with TBT's and recalcs behave very fine for me. But using the device very basically - only 2 sensors (non-Garmin HRM, old GSC10 speedsensor without cadence magnet), no connection to smartphone, no IQ apps. Always synch USB wired to Garmin Express on the PC (Windows 10 Home 64-bit US).

@bikepc01 Have you done factory reset?

I am using it without sensors or IQ maps. I am trying to keep it as simple as possible.

No factory reset after any firmware upgrade. The only thing I do is keeping the number of files on the device as small as possible - Activities, Courses, Calcs, PointCache. Calc and PointCache are filled with .cal resp. .gpc files for every Course file uploaded to the device via NewFiles and PointCache gets another .gpc file after finishing the ride & saving the activity.
If there are near 100 courses, 100 Calc files and 200 PoinCache files the device get slower, specially after it transfers files via MTP. My impression is that also the internal household of the EE2 is slower now with MTP, but no issue while cycling with TBT's.