Ads by info is a virus that gets into your browser. What browse are you currently using?
You will need to go into your control panel and remove ads by info from your program list. Run CCleaner after it is done.
Here is a link to a removal guide. Don't click on any of the links on the page...they just want you to buy stuff. Just read the text and it will show you how to remove it.
http://malwaretips.com/blogs/ads-by-info-removal/
Cheers
Col