windows update question

I have a vista home basic laptop running NIS 2014 v 21.
I have taken to delaying downloading and installing windows updates given some of the problems thay cause. I will usually wait a week or so before installing.
Well usually when I check for windows updates this little machine will take a while to find updates. So I’m use to waiting. So yesterday I went to check for updates and shortly thereafter a message indicating unable to find updates and an error code was given. I dont recall the error code now but when I looked it up on the microsoft site, it seemed to indicate that updates could not be found and usually it was because of some type of infection blocking the updates. so in a panic a attempted to run a manual NIS live update. That worked fine without probem. So I thought if I was infected wouldnt the infection stop my NIS from updating? So I thought this was weird. So I attempted to run Microsoft updates again and the same thing happened as before with same microsoft error message. Well I thought tis must be not due to an infection. So I tried to run microsoft updates a 3rd time and was successful in getting the updates that normally come on patch Tuesday.
So I am thinking my machine is NOT infected and that it was just some kind of glitch
I wanted to get some feedback to see if I am correct taht it was just an abberation since My NIS was able to update and I was able to get the Microsoft updates.