Previous backup after Windows 10 update

Hi,

I've been using acronis trueimage backup 2014 then upgraded to acronis trueimage backup 2015 and keep backing up my Windows 8.1 machine

Yesterday I've installed Windows 10 and the installed acronis trueimage backup 2015. I was hopping to retore my files from previous backup (VBK and VIB file extension) but there is no way to open it and explore. New backups are working (I can open them and browse).

How could I access to the files from my previoous backup (before the complete machine install)

Regards.