If your forum does not allow attachments to be viewed by guests (not logged in), guests will not be able to view embedded attachments.
I had tried enabling attachment downloads for guests earlier, but it didn't seem to help me see the embeds at the bottom of page 2
Right now they are enabled for Guests and I can see the new one I did today on page 3, but not the older one at bottom of page 2.
Signing on as a member it is the same way.
If I sign on as Admin I can see them both.
Can you see embeds on bottom of page 2?
https://www.electrical-contractor.net/forums/ubbthreads.php/topics/220154/2.html