This just started recently. When I upload an attachment it gives me "The connection was reset". If I upload a REALLY small attachment it gives me "Upload of file failed."
I haven't recently installed any modifications to my knowledge. Anyone else had this problem?
I suggest you start by posting in the server configuration forum at vBulletin.com and see if there are any server configuration parameters that need to be changed. If that doesn't work, then i suggest you open a support ticket.