sCHEDULED FULL SYSTEM SCAN DOESNT RUN NOW

I have a scheduled full system scan set to run a few times each week. I have noticed today that it has not run since 2/2/16 (today is 2/11/16), so it has been over a week. The quick scans still run whenever virus defs are updated. I am able to get my updates automatically. Just that my scheduled full system scan doesn’t seem to run/initiate. I can do a manual full system scan, but not a scheduled one. My date and time are correct. I have shut my PC down and waited 15 or so minutes and then restarted my PC hoping that would work. But it doesn’t
Any ideas as to what is happening/what I should do?
I have a Vista Home Basic laptop and use NIS 2014, old school style.