Kind of a workaround for now...
1. Zip up your Excel file. It must be in zip format.
2. Email it to (mrexcel@fuse.net)
3. Make sure that “MrExcelPostFile” is in the subject (without the quotes)
You should get a reply shortly with a URL to copy and paste directly to the board.
From this URL, you should be able to download the atttachment you sent too me. I created a script in Outlook to watch for emails with attachments that contain “MrExcelPostFile” in the subject. If so, the script is supposed to automatically upload the attachment to a web server and reply with the URL. If it works, you are welcome to post as many attachments as you wish.