Are rural? Do you have high speed internet connection?
Have you sent pictures to others before?
Have you sent pictures to the board before?
All these might be indications of your problems.
When you've tried to attach your picture, have you noticed whether the light gray box next to the word "Browse" has words in it? This will tell you that the attachment made it from you files into the post.
After you've clicked "send," it may take a while -- up to a few minutes -- for the picture to "arrive" on the board. Be sure not to click your "back" button during this time, wait for the page to come up automatically.
Is it possible you just have not allowed enough time?
Jan in VA