OK I know this is may seem silly, but I had to test this. I had problems uploading an image last week, and gave up in frustration. I also had someone ask how to do this, so here's the post.
The images below are from 3 different sources: Left - Photobucket, Middle - SkyDrive (through Hotmail/Outlook - MSN) and Right - Mediafire.
I think it was just a website hiccup I was getting that day from the when I was having problems, because it seems to be working now. For those of you who haven't posted a picture or image on our website, it is done through URL links to other websites or online storage: i.e. Photobucket, Mediafire, SkyDrive (Associated with MSN's Hotmail system - now called Outlook online), deviantART and others. Anywhere you store the picture online, will generate an actual web link for that image (test it by right clicking an image online, going to properties at the bottom of the popup:
In the middle of the image above, is the URL web address of the right hand image of my character Derkra. In the Icon bar of the Forum Post Editor is the symbol for inserting an image (middle of the second row: ).
The source should be the "direct link to embed" an image from the storage website to the one you wish to post on (this website). Some storage sites will say just Direct, others have tabbed selections one of which is to Embed, like with the Fleet Mediafire account:
I click the Embed button at the bottom, it changes screens and I choose the URL labeled "Direct". Once you copy and paste the URL in the Source box for inserting the image, you need to click in the "Image description" you don't have to type anything, but numbers should appear in the Dimensions boxes. If you get the numbers, you're great; if not, you copied the wrong link. Find the proper "Direct' URL link from your storage site an try again. And, that's all there is to it. If you have further question, send me a PM and I'll try to help you out one way or another.
Happy Hunting!
JT