DataProtector 7 to 9 upgrade problem

Hi all,

Recently I have upgraded our DataProtectorv7 to version 9. But after that all devices and pools disappeared from Devices &  Media menu. I tried to rollback upgrade. Uninstalled version 9 from the CM machine and installed DPv7 with old database. But after installation DataProtector CRS service didn't start at all. Does anybody faced this issue? How can I save my backups ? Please help me, any help would be great !

Thanks