Boot options win 8.1

I have a Kaspersky rescue disk that scans everything for viruses. But, I cannot boot with it to get it started in Win 8.1?

Most likely something to do with UEFI(a secure boot technology that in effect, means it’s difficult to boot anything other than the installed Windows OS). It can be disabled, at your own risk.

See:
http://support.kaspersky.com/9722#block1