del "F:\Backups\Backup Files\backup7.bkf"

ren "F:\Backups\Backup Files\backup6.bkf" backup7.bkf
ren "F:\Backups\Backup Files\backup5.bkf" backup6.bkf
ren "F:\Backups\Backup Files\backup4.bkf" backup5.bkf
ren "F:\Backups\Backup Files\backup3.bkf" backup4.bkf
ren "F:\Backups\Backup Files\backup2.bkf" backup3.bkf
ren "F:\Backups\Backup Files\backup1.bkf" backup2.bkf
ren "F:\Backups\Backup Files\backup.bkf" backup1.bkf