Judith, it might be easier to post your pictures in the EPP Grand Illusion group photos if you have joined that group. It sounds like you are trying to post from within a message.
Any time I post something that just "disappears", I refresh my browser and it appears. Also, If we find ourselves sending the same thing a million times, as the author, I can delete a message or notification from the Connect/TQS Community page.
Please note, that I was not able to post a picture because I had an apostrophe in the descriptor. I'm not sure all punctuation marks would do the same, but it's easier to just get rid of them that have errors thrown.
Example: Ellie's Quilt.jpg would not upload. Ellies Quilt.jpg did upload.