I am getting this same error "The Specified file was not found" when I am trying to open an attachment in QB.  I CAN open the company file.

I tried the first suggestion on this thread and it does not solve the issue.

I tried to follow the second suggested solution and get lost after going in to the security in the QBW32.EXE after EDIT and ADD.  I don't see where I need to set it to EVERYONE

I attach a scanned pdf file to a transaction, customer or vendor.  When I go in to the transaction, customer or vendor and click on the paperclip attachment after I attach it, it shows the file there but when I click to open it I get the error "The specified file was not found" and can not figure out how to fix it.    

I am using QB 2015 Pro desktop software.  It has done this since 2017.  I get the same error on a WIN 07 or WIN10 machine