Vista backup disks and files are not usable in XP. Microsoft from what I can tell is not releasing a tool to read or restore from their new backup program (in XP.)
To work around this, be sure to backup the old fashioned way. Such as recording the files you want to closed session CD or DVD media or even copying to an external drive using nothing more than Explorer to copy the files.
If you feel this is not a good answer, please call Microsoft. They need to not slam the door on XP so fast.
Bob
I was running Vista home premium when my system started to suffer for different reasons, so i decided to go back to xp media center edition 2005 for the time being. I backed up my files on vista not realising that it wasnt so easy to restore them in xp. any ideas as to how i would be able to restore my files on xp from a vista backup?

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