Opening a .ptb backup file from new client

SUGGESTED

In search of some guidance. I have a new client that uses Sage 50 (version 29.103). They have sent me a backup .ptb file, and I'm trying to figure out the best next step. I don't currently have Sage 50 on my end, but I did sign up online for the free Accountant edition. Do I need to purchase Sage 50 to open the .ptb file? Or is there another way I can restore this file?