回答“htc desire hd not turnig on since last charged”Change your battery.
回答“Network wifi lan problem and volume bottons”Here, you can try this fix:Fix HTC DesireHD Signal problem
回答“My phone stuck on HBOOT”Weird. Why don't you use a tool instead of trying with the buttons. Check:Easy Ace Rootkit Still seems a malfunction of the board, but you can try. In the worst case you can get a replacement of the board. Saludos.