In reply to a post by BatBoy:

http://www.isobuster.com/udf-reader.php

I should have qualified my comment- "that was free"

https://www.roxio.com/enu/support/udf/software_updat...

Missed that one

OOps - I've got a Sony HDD/DVD recorder myself which makes the fact that I just assumed it was a laptop or PC that was the subject of your post even more embarrassing for me. Sorry I can't add anything useful.

Think you may be on a hiding to nothing to find suitable software to decode the files.
Surely the easiest way is to buy another working SONY RDR-HXD710 on eBay, swap the drive out and record to DVD. Seem to be around £75 for a working model.
Once you've backed up to DVD to use on your new Panasonic, you can resell the Sony for a similar amount, less fees of course. Only other cost is 20 odd DVDs, which are as cheap as chips nowadays.
Probably the easiest, cheapest and least stressful solution to your problem.

In reply to a post by rogerfp:

Think you may be on a hiding to nothing to find suitable software to decode the files.
Surely the easiest way is to buy another working SONY RDR-HXD710 on eBay, swap the drive out and record to DVD. Seem to be around £75 for a working model.
Once you've backed up to DVD to use on your new Panasonic, you can resell the Sony for a similar amount, less fees of course. Only other cost is 20 odd DVDs, which are as cheap as chips nowadays.
Probably the easiest, cheapest and least stressful solution to your problem.

THAT IS JUST BRILLIANT!
Why did I not think of that?
My brain must have gone into neutral - age related decay?
MANY THANKS.

You are most welcome.
Sometimes I think we all try to overthink things. I know I've done it many times.
Then suddenly there is that "lightbulb" moment and everything becomes clear.
Nothing to do with age, I assure you.