I suspected a harware fault, one of the things i like about HTC phones is that they have a 2 year warranty.Mine runs out in November, I will put the stock rom back on and send it for repair, but I remember reading on an older thread HTC will not repair phones that are S-Off, will I need to try and get it back to S-On if possible?
I don't have this problem, the OP does - and this thread is from 1/2 year ago, so I don't think he'll see it to answer the question...
There's nothing to do with physical USB socket failure but to fix it. If you're HTCDev-unlocked and want to relock - unfortunately you're out of luck, and you won't be able to change ROMs either, not being able to fastboot flash anything.
Have you tried more than one PC?
Have you tried more than one USB cable?
Did you ever instal HTC drivers? You should find HTC sync exe in root of sd card
And just to correct a possible typo in the post above
- rename it to "PG88IMG.zip" (case sensitive)
- put it on the root of your SD card
- reboot into hboot and wait.
I don't know what is "USB brick", but there's no such thing. While you can screw up USB access in the OS, there's no way you can screw it up in the bootloader. If you read well and put attention, you'll see that all "USB brick" threads in Desire were in OS, and fastboot worked. The most likely reason for USB not working in fastboot is physical - one of the USB pins disconnected, either bent inside the microUSB socket of the phone (most likely), or broke off the main board (less likely). So the required fix is physical as well.