You’re trying to restore a backup, but it’s greyed out in the Archive Database, and unavailable in “Restore from VD” wizard.
Sometimes .pfi file could be damaged or corrupted or deleted somehow so restoring we get troubles. This problem could be fixed rebuilding backup.
Archive with such index file will become alienated, and it will not be possible to restore it to original location (only by erasing the source disk). Besides, if there are increments based on this archive, it will not be possible to restore them anymore – original .pfi file is required for them to work.
Launch Restore Wizard and Switch to File View
Change Files of type to All files, then navigate to the backup folder and select the .pvhd file (or .vhd, .vhdx, .vmdk – depends on the archive type)
Rebuild the .pfi file by pressing Yes when prompted
Now you can either proceed with Restore by pressing Next…
…or quit the wizard and check the Archive Database to see if the entry is now present in the list.