I donwloaded the SERT and burned it to a CD. It wasn't clear on the virus definition update page how you specifed Rapid Release vs. Daily Certified, but I found a download file corresponding to the SEP Small Business 12.0 for 64-bit Windows (vd34fe03.jsp so I downloaded that and extracted it to a USB drive.
The computer boots up fine from the CD, but the scan uses the old definitions from the laptop. How do I direct it to the USB drive? Do I need to install from the USB drive first by booting from it?
TeeJay