All fixed now!
Downloads were not enabled in the Read only forums which I have turned all those on for downloads.
Please let me know if you find any that you can't view attachments. This is open even for guests.
Thanks so much for pointing out the error!!
This was actually because of an upgrade to a newer version of the Board software done last March. The attachment system was completely overhauled and it included a new "permissions" area for enabling downloads (which wasn't in prior versions). When they added that it is disabled by default and I completely missed that. So it was probably occurring between March and now which until someone reported the problem, I wasn't aware of it because I rarely view the forums on a member or even guest level. Maybe I might try to remember that next time there is an upgrade