Default ADB/FASTBOOT= Device not Found (Try These)

Right....So your main issue is “device not found in ADB and/or Fastboot”

Adb commands only work when you're booted in the rom or recovery***** Fastboot commands only work when youre in bootloader

Here is a few simple things you can try:

*Try a different recovery.
*Try a different usb data cable.
*Try a different computer.

and this ..a little more time consuming..

*Try this (obviously delete previous adb/htc sync/drivers etc)
If running windows 8 or above there is a fix in the above link...just read!

*Revert back to windows 7.

*Download “Ubuntu” and run on a livecd ( then connect phone and do what you have to do.

*last resort look into things like this :

***If anyone has another solution that works i will update the above****
Htc One Mini | PAC-man | TWRP | HBoot 2.22 | S-OFF | SuperCID | Gapps by BaNkS

Htc One M7 | Candy Kat Rom | TWRP2.7.1.1 | HBoot 1.57 | S-OFF | SuperCID | PA Micro Gapps