Hi Blackburst,
are you still experiencing issues? How large was the file you tried to upload?
I ask this as recently the majority of my forum stopped displaying and it was due to an avatar image someone tried to upload. Once I had removed the file which was about 3mb in size, everything loaded up correctly again.
Assuming your issue is something similar. Go into your your FTP client and go to /wp-content/uploads/06 (assuming it was in June that the error occured, it says posted a week ago) and delete the image you uploaded.
