I have a forerunner 910XT (<2 years old). I use it regularly, and today when I tried to load my workout, it wouldn't transfer the file. I tried troubleshooting, and I get a message from windows "The last USB device you connected to the computer malfunctioned and windows does not recognize it." I found some threads that recommended going to device manager to re-install the driver, but the computer doesn't recognize the ANT stick at all. I tried every USB port (on 2 computers) and re-booting. I don't think it is Windows 10 since it has been working on this computer for several months. I have a feeling the actual stick might be corrupt, but I'm wondering if any users have seen this problem or have suggestions.
I didn't get (or at least, didn't notice) the "last usb device you connected malfunctioned" error, but I have got an anti+ stick that Windows is refusing to see - Garmin Express just gives "ANT Stick Not Connected" errors. Same with all USB ports.