Reducing the size is not the correct solution. I tried to upload three pics last night in the Nikon P Series subforum as part of a longish post. Two of them got through okay, the third showed the dreaded "attachment... ". When that was clicked, it went to a "broken link" message which included and option to message the site admin. HA! Apparently the message went to wherever the missing pic is or somebody got it and chose not to reply. But since the later is so ill-mannered, I choose not to believe that anyone with any responsibility whatsoever would do it.
The three pics were all straight out of the camera, 4000x3000ppi. Two went through okay, so it's not the size. Also in preview, everything looked fine. It was only after I hit "post thread" and then looked at the post that I realized it had been ruined.
I'm using Chrome, have no trouble uploading pics to any other site, have emptied my cache and cleaned up the area around my computer, applied deodorant and am always clean and polite and most of the sores have healed up, so IT AIN'T THE DAMN USER'S FAULT! Something is wrong with the site software. Duh!