What do these queries return?
SELECT COUNT(1) FROM msdb.dbo.backupfile;
SELECT COUNT(1) FROM msdb.dbo.backupfilegroup;
SELECT COUNT(1) FROM msdb.dbo.restorefile;
SELECT COUNT(1) FROM msdb.dbo.restorefilegroup;
SELECT COUNT(1) FROM msdb.dbo.restorehistory;
SELECT COUNT(1) FROM msdb.dbo.backupmediafamily;