A well encryption can't be broken without knowledge about the encryption passwords, keys etc.
trying to decrpt is a useless effort, discuss your needs with the vendor of that barcode program.
To add to jrbbldr:
"If you have a legitimate reason to open a file which was intentionally encrypted by someone else, please let us know."
You'd need to provide a proof of that legitimate reason, before I'd even touch this download and even then the cahnces to decrypt this are very bad, you better solve your problems with this vendor.
I can't believe he will refuse to sell you more functionality or licenses or whatever you need.
Bye, Olaf.