Does this sound like what you are seeing right now? You see pop-up ads from s.popitunder.com while browsing websites that typically don’t advertise in pop-up windows. The pop-ups manage to sidestep the built-in pop-up blockers in Chrome, Firefox, Internet Explorer or Safari. Maybe the s.popitunder.com pop-ups appear when clicking search results from Google? Or does the pop-ups show up even when you’re not browsing?

Here’s a screen dump of the s.popitunder.com pop-up ad when it showed up on my machine:

Does this sound like your machine, you most likely have some adware installed on your system that pops up the s.popitunder.com ads. Don’t blame the people that runs the website you were at, the ads are presumably not coming from that website, but from the adware that’s running on your machine. I’ll do my best to help you remove the s.popitunder.com pop-up in this blog post.

For those that are new to the blog: Recently I dedicated a few of my lab machines and wilfully installed a few adware programs on them. I’ve been observing the behaviour on these systems to see what kinds of adverts that are displayed. I’m also looking on other interesting things such as if the adware updates itself, or if it installs additional unwanted software on the machines. I first found the s.popitunder.com pop-up on one of these lab computers.

s.popitunder.com was created on 2015-04-26. s.popitunder.com resolves to the 195.93.85.27 address and popitunder.com to 176.10.250.18.

Thanks to YouGetSignal’s reverse IP lookup service, I could see that the following domains where located on 195.93.85.27:

• s.vgsgaming-ads.com
• www.abuse.ch

So, how do you remove the s.popitunder.com pop-up ads? On the machine where I got the s.popitunder.com ads I had Windows Menager, SmartComp Safe Network, gosearch.me and Live Malware Protection installed. I removed them with FreeFixer and that stopped the s.popitunder.com pop-ups and all the other ads I was getting in Mozilla Firefox.

If you are wonder if there are many others out there also getting the s.popitunder.com ads, the answer is probably yes. Check out the traffic rank from Alexa:

The traffic to popitunder.com has boosted enormously since June 2015.

The bad news with pop-ups like this one is that it can be initiated by many variants of adware, not just the adware that’s installed on my machine. This makes it impossible to say exactly what you need to remove to stop the pop-ups.

So, what can be done? To remove the s.popitunder.com pop-up ads you need to check your machine for adware or other types of unwanted software and uninstall it. Here’s my suggested removal procedure:

1. What software do you have installed if you look in the Add/Remove programs dialog in the Windows Control Panel? Something that you don’t remember installing yourself or that was recently installed?
2. You can also review the add-ons you installed in Chrome, Firefox, Internet Explorer or Safari. Same thing here, do you see something that you don’t remember installing?
3. If that didn’t solve the problem, I’d recommend a scan with FreeFixer to manually track down the adware. FreeFixer is a freeware tool that I’m working on that scans your computer at lots of locations, such as browser add-ons, processes, Windows services, recently modified files, etc. If you want to get additional details about a file in the scan result, you can click the More Info link for that file and a web page will open up with a VirusTotal report which will be very useful to determine if the file is safe or malware:

   

Here’s a video tutorial on how to remove the pop-ups with FreeFixer:

Did this blog post help you to remove the s.popitunder.com pop-up ads? Please let me know or how I can improve this blog post.

Thank you!