Restore folder isn't complete

hi
i am having two program backup for the same ABB robot, with same configuration. We did the new programming recently with a new module.Now we tried to restore the old backup. But it is showing that 

Unable to perform the restore request

Reason:
Restore folder isn't complete

we didnt changed anything on the backup file and also we didn't changed any robot configuration also. 

Any help is appreciated. (looking for immediate response)