Winkey

[Jan (Microbit)]

What?! Are you still talking about the USB ports in the RRC? I am asking since those drivers have not changed a bit since the first version of Setup Manager as they actually are provided by Windows itself. The only difference is that we have added signing to the so called INF files which is used to link Windows's driver with the RRC's port making it possible to install on Win 7/8 64 bits without bypassing the driver signing requirement.

[oh2xx]

I am talking about the USB drivers that come along with the setup manager installation package.

E.g. I can see that the name for "RRC1258 COMExtra"  has now changed to "RRC1258 COMFSK" in device manager after downgrading.

[Jan (Microbit)]

I had to check what more could be the explanation to this strange behavior and found out that there have been a couple of changes made to the INF files besides the signing, changes which Microsoft recommends to make sure the USB COM port driver they provide is installed and found on every type of Windows. (As I said, we do not deliver a "driver" since the driver in question belongs to Windows itself, we only provide a file which tells Windows that we want it to use its driver with the RRC).

If now in fact those changes instead have made the system unstable and not working as good as before then it is truly nuts! We will certainly have to look into this!

Thank you for your help and patience!

[Jan (Microbit)]

After digging deep into this I still can't see why the changes we did to the INF files as per Microsoft's recommendations could break the functionality like described in this thread. It is like there is not only the possibility for a device to fail installation but also to install successfully yet not work, or at least only work partially.

Unfortunately we do not have computers showing such behavior here at Microbit, which makes debugging hard.  If I try altering the INF files would it be possible that you Kari do some testing to see what happens?

[Jan (Microbit)]

I have done a few more attempts/tests but still I fail to find any difference between the old INF files and the new ones. The ports are installed and works. Very strange...