I did some tests to regain the band 42 support, this is where I am now:
- First tried to restore the factory state:
This was successful, but still the modem wont register with our network.
- Created my own band setup with only band 42 in it:
The modem was registered successfully (01.00.02.00)
- Upgraded to 01.05.01.00, after upgrade again there is no band 42 support, creating my own band solved the issue again.
This is where I am now.
I noticed that from 01.05.01.00, I need to go to 01.07.02.00, before I can get to the latest one.
So this is a partial success. Will continue tonight.
@mlw by the way the company said they cannot send the tool you mentioned to me. In case I really need to use, I will need to send the modem back, which I find ridiculous.
I continued on my journey, and upgraded to 01.07.02.00.
Of coarse, there was no band 42, but I noticed that AT!IMPREF? returns a “config name mismatch”:
preferred fw version: 01.07.02.00
preferred carrier name: GENERIC
preferred config name: GENERIC_002.004_001
current fw version: 01.07.02.00
current carrier name: GENERIC
current config name: GENERIC_001.028_000
config name mismatch <--- !!!
In this case, the same firmware version needs to be flashed again, as this indicated some NVRAM compatibility issue.
I reflashed the firmware, and the “config name mismatch” error was gone.
Finally, I flashed the latest (01.08.04.00) firmware, which was a success (no reflash was needed), yet no band 42 support.
Now I set my band profile again (which was lost after the FW upgrades):
And after the reset, the modem is now registering on band 42 with the latest firmware.
I would highly recommend this page, as it contains many valuable info for the EM module type: