copied from the message before I posted:
Ok, "Re-encode potentially dangerous image attachments" is now un-checked. And here comes the test.
And same result! Darn, I thought that would be it.
Well I don't know how to get the file to you, except by email.
Hhmmm..... Oh wow! I found the file in the Attachments folder! It looks like it might be in there 3 or 4 times, each time I tried to attach it! Looks like numbers 144, 149 and 150, if you can get the files from there? Oh, and that's the Attachments folder in the server File Manager. But it's NOT shown in the Attachments list in the SMF Admin section. A clue, perhaps?
(I don't think it will help to insert the image into the msg, but I can if would help.)