I'm not sure if it charges while in bootloader (not hboot), but leave it connected for a few hours and try again. I don't think that's your problem though. Have you tried just rebooting the PC? Or tried on another PC?

Sent from my Evita
HTC Evita | CandyKat | Torched KK
S-off | 2.18 | TWRP 2.7.1.0
Do not PM me asking for assistance, that's what my Q&A thread is for!