I had the same issue with 2.7.12 and a Trezor on Windows 10. Trezor worked fine at mytrezor.com and also worked fine with electrum on a Windows 7 machine, just did not like Windows 10.

However I fixed it by getting Windows 10 to forget the Trezor and redetect it by running a utility USBDeview ( http://www.nirsoft.net/utils/usb_devices_view.html ).

It shows a list of connected USB devices and can be sorted by last plugged in making it obvious which device was the Trezor, right clicked and uninstalled the device. Then plugged the Trezor back in, Windows re-detected it. and everything worked properly.

My suspicion is that updating the firmware somehow confused Windows, as the Trezor was working fine before I updated. All works now though.

If I have learned anything from bitcoin, it is to buy low and sell high.

The coin always rises.

Noob account here, lurking here since BTC was less than $1.00. Anyhow, chiming in just because I finally registered.