Windows 10 not recognising watch via USB all of a sudden!

Hi folks

Windows 10 (on 2 different laptops) stopped recognising the F5X+ as a USB device all of a sudden. I get the dreaded "USB device not recognised" error on both machines.

Watch running original/stable firmware. Latest version of Express. Have tried in Garmin & MTP modes. Windows errors on connecting the watch as per above. Express does not see the watch at all.

Have tried every single troubleshooting step on these forums & from Garmin's support pages. Nothing works. Only thing I haven't done is factory reset the watch for obvious reasons.

When I go into Device Manager in Windows, there is an error next to one of the USB devices (device mlafunctioned). As soon as I unplug the watch, the USB device with the error disappears.

USB mode was working fine last week. I have not changed anything on the watch or the PC in that time.

Any ideas or is anyone else having this issue?