not really sure how this happened but how do i fix it?

For one, use a gif, jpg or png format. Bitmap's are way too bloated.

And you wanted access to other people's computers? Wow...

Looks to me like you were playing with ResHack and screwed up your explorer.exe

You can also try actually researching things like how to make proper backups before you modify any files on your computer. Try a System Restore, then go read about how to work your computer.

1) i wanted to access my own files and i figured out how to do that by sharing it on the network then going through my IP to open the folder.
2) i havent used any res hackers and i didnt touch explorer.exe.
im not dumb enough to start messing with my explorer.exe.
3) that doesnt help me solve my problem.
4) my friend had the exact same problem as i did.
i just dont know what program did it.

Riiiight. It's obvious you used a program (malicious or not) that changed, replaced or modified your explorer.exe

Start > Run > sfc /scannow