Achieved S-off, Windows & MacBook won't install correct driver

I obtained S-Off on my One M8, but whenever I hook up my phone to a PC or Mac, it won't let me access anything on the phone. adb won't work, I don't get the option to select MTP, and the phone still charges. I got error code 43 on the PC, and I've tried installing HTC Sync on both to no avail. Any other suggestions at this point? I really only need to do this in order to get a custom recovery on my phone.