You selected one or more drives that contain existing backups from the server {0}. Either you can keep the existing backups ...

You selected one or more drives that contain existing backups from the server {0}. Either you can keep the existing backups for future use, or you can allow the wizard to reformat the drives and delete the existing backups.

Drive with existing backups:

{1}

Click Yes to keep the existing backups.
Click No to delete the existing backups.
Click Cancel to go back and change your backup drives selection.