Htc one v problem

hello, first of last version (i say 3.5...) my htc one v works well with unity android. Now i have a licenze pro but my pc say always that no android device was recognized. But..i use well my phone via usb port and the same pc. I can copy on its memory for example. So anyone know a solution? I must copy .apk every time and install it with an apk installer it's frustrating!