Unable to access backup from a new computer

We backedup our old computer using a WD passport 2 or 3 years and then promptly forgot about the passport.  2 or 3 years on, the old computer gone and a new computer in place I need to find a file which I think is on the backup.

Linking the Passport by USB to the new computer, the passport is recognized, but I cannot review or restore the backup files.  

It occurs to me that I probably need some WD software on my new computer.  I no longer have the user instructions and cannot remember if we had an install CD when we first used the passport on the old computer.  Cannot find any CDs in the draw.

Is this the problem and where do I find the software, there is a trial version sitting on the passport.  Do I use this ?

Clearly a novice user !

Thank you ?

well…

you don’t need any software to retrieve the files if you used a backup software…

Totally different ball park if you used a sync software…

can you please check on the drive to see the folders you have there… you will see the backup folder with all the data

please verify what software you used and/or more information about the drive like the model number