Originally Posted by sugarshock
Is there another way to access my phone (maybe through wifi) that gives me access to every file and folder?
Airdroid will do that but I'm a little skeptical that it will work if it's not being recognized by the PC.
I know you've beat this to death already but just to be absolutely sure, you are also checking for connection by viewing your drive list at "my computer" right. Cuz being an HTC device, it should register two drives as letters. One for your internal memory and one for the sd card.
Some other thoughts. Nice job on the self troubleshooting. You really did try about everything on the list of usual suspects. Have you tried it on another computer though to rule out some odball thing with your PC? Also, how about connecting another device to that PC. Will it recognize another phone, ipod, mp3 player, digital camera, anything at all?
edit: well your post above pretty well rules out any storage showing up as a drive.