Thank you for posting your query in Microsoft Community.
Based on the information you have provided, I understand that you are getting s.ytimg.com pop-up while watching YouTube videos. I will certainly help you with this issue.
Please follow the methods.
Follow the steps and check.
a) Point your browser at a flash video on a site you are concerned about (such as YouTube) and right click on the video's timeline bar.
b) Select "Settings", this will bring up the Flash Player's settings.
c) Click on the privacy tab and make sure the settings are set to "Deny" and "Remember".
d) Click on close
I would also suggest you to download and run the latest Microsoft Safety Scanner on your computer and check if it helps:
Note: Any data files that are infected may only be cleaned by deleting the file entirely, which means there is a potential for data loss.
For assistance with issues related to Windows feel free to post on Microsoft Community Forum.