Unable To Change Ownership (New Computer) Mounting ATI-2015 no R/W Support

I purchased 2015 for a Client to back up a dying computer. When I moved ATI-2015 to his new DELL, (after attempting to restore Factory OS on Old Computer), I could not take ownership of TIB backups.

I read the KB article that Mount R/W is no longer supported. How is it this can be removed, when moving to a new operating system and computer and you cant access your files in previous machines backup? When I read this I was in disbelief!

I brought it to my office, and used MY older version of ATI and mounted using R/W to change Permissions. I moved his files to a general folder on the EXT DRIVE (used for backup). I will be visiting client tomorrow, but I didn't realize that this feature was removed. You basically locked out a new computer from taking control of a backup.

Am I missing something here?