Restore Media Jukebox v 8
Restore Media Jukebox v 8.0.393 or higher*
To restore this version of Media Jukebox (available on the download page) after having installed Media Center, simply install Media Jukebox and it will detect the backup copy of its data created when you installed Media Center. When it offers to restore that backup, simply say yes.
*This build of Media Jukebox v 8 does not include TV or DVD, which were moved to Media Center v 9.
Restore Media Jukebox v 8.0.388 or earlier
Media Center will have created a backup of your Media Jukebox data files in the following default folder (it will be different if you installed Media Center in another folder): C:\Program Files\J River\Media Jukebox\Data\Media Jukebox 8.0 Upgrade Backup. Before installing Media Jukebox v 8, manually copy the *.jmd files from the backup file to:
C:\Program Files\J River\Media Jukebox\Data
This assumes you will be installing Media Jukebox in the default folder.
Then install version 8.