My browser seems to be infected with some sort of spyware/virus. To be specific, an advertisement keeps popping up in the lower right and left hand corners of my browser. No matter which site I visit , they are always popping up and sometimes even redirecting me to Norton's antivirus product page.
I have AVG, Malware Bytes and Spybot installed and kept up to date, have ran multiple full scans even in safemode, but nothing is being detected by them.
I've also tried uninstalling and re-installing bot IExplorer and Firefox , but the same thing still happens.
Does anyone know what I'm talking about and how to fix this ?