Update (August 2016)
Please take a look at these updated instructions on Github to troubleshoot issues you have with Windows and Tessel 2.
Older instructions (pre-August 2016)
A holdover fix for Tessel 2 drivers on Windows:
Download and unzip the archive on this gist,
Open a Command Prompt in the newly unzipped folder using Run as administrator.
Unplug Tessel 2 from your computer.
Hold down the reset button near the edge of Tessel 2 (by the antennas). Plug in Tessel 2. It will now be in DFU mode.
Tessel will reboot and working Windows drivers will be loaded. In about 30s, run
t2 listto see if this was successful.
Having run the above steps, your computer will have uninstalled the old Tessel 2 drivers. Tessel 2 is now flashed with firmware that works on Windows out of the box.
NOTE: A Tessel 2 with updated firmware can use
t2 update as normal. You do not need to repeat the above steps on a new computer that has not been exposed to the old firmware.