troubleshooting connectivity issues:
-try a reboot of the PC
-try different usb cables and ports
-dont use a usb hub
-dont use usb 3.0
-make sure nothing capable of comunicating with the phone is enabled and running. htc sync,pdanet,easy tether,and even itunes have all been known to cause issues.
-windows 8 has been known to have issues. try a windows 7 or older machine
failing the above,
-i use these drivers for fastboot and adb(donwload and run as admin):
http://downloads.unrevoked.com/HTCDriver3.0.0.007.exe (
mirror)
failing that,try manually updating the drivers in the following manner:
-put the phone in fastboot mode(select fastboot from the hboot menu)
-open device manager on the PC
-plug in phone,watch for it to pop up in device manager.
-update drivers with device manager,pointing the wizard to the
extracted
driver download folder from above
note that you can check the connectivity of the phone,and make sure drivers are working by in the following manner:
-open cmd window. change to directory containing adb/fastboot utilities
-
adb with the phone in the booted OS,usb debug enabled,enter:
adb devices in a cmd window
-
fastboot with phone in fastboot,enter:
fastboot devices in cmd window
in either case,a properly connected phone with working drivers installed should report back the phones serial number.