[Q] Problems with adb/fastboot after updating to Android 5.0.1 topic

I recently updated to Android 5.0.1 on my M8 GPe and it seems to work just fine. Today I wanted to flash a custom recovery but I couldn't get any connection between the phone and the computer. When I enter fastboot I don't get "fastboot usb" as I usually do.
Do I need new drivers or something? I have both Windows 7 and OS X 10.10 so a solution for either is ok.