Attaching files here?

I have a question that is best asked by attaching either a .dorico or a .pdf file. For some reason I’m unable to do either (using Add or moving the file to the message box) – getting the ERROR message “Invalid file extension: Example.dorico (or .pdf)”. Both files open without trouble on my PC. Has anyone else had this problem? Am I doing something silly? https://www.steinberg.net/forums/posting.php?mode=post&f=246&sid=1a06d3c00c422a6d921ce976f291698b#
–N

I believe phpBB restricts the kinds of files you can upload. To upload a Dorico file, you’ll have to zip it first. I’m not sure about the .pdf, but it’s most likely the same.

Files have to be zipped up (or in .png format). I’ve heard that you can upload a Dorico file if you add a .zip extension to the file name, but I haven’t verified that to be sure.