The fact that the virus scan fixed this problem at least for a little while tells me a lot. This sounds like a browser hijack.
What’s a browser hijack?
A browser hijack is a type of malware that infects your system. Once downloaded, it waits until you do an internet search; when it sees a page with search results, it updates the results with its own links to advertisements or other websites. No matter what you click on, you see what the malware wants to show you.
If you’re just getting pop-up advertisements, consider yourself lucky. Sometimes, people get redirected to more damaging stuff.
So how do you deal with it?
Fixing browser hijacks
You definitely want to treat this as malware. My first suggestion would be to make sure you’re running up-to-date anti-virus and anti-spyware scans.
It sounds like whatever tool that you’re using worked once before, but I would also consider running Malwarebytes, a free tool available for download at malwarebytes.org. In my experience, Malwarebytes does a good job of catching things that other anti-malware packages sometimes miss.
Once the malware is gone, you want to think about how this happened so it doesn’t come back.
Where is the malware coming from?
If your anti-malware tools removed the malware, but this browser hijack keeps coming back, then you might be doing something to invite it back on to your system. For instance, a browser hijack may happen to someone because they’re:
- Downloading files or visiting sites that they shouldn’t be.
- Turning off their real-time anti-malware protection.
- Using lower quality anti-malware software.
There are many possibilities.
This kind of hack could also happen indirectly. For example, you may visit a website that’s been hacked; it looks fine, but some hacker modified it surreptitiously so it actually downloads malware on your machine.
A website hack is something that most website owners (like me) fear because hackers can target just about any website. It could be a site that you know and trust or one that you’ve simply used for a long time. Although website owners and moderators take steps to prevent these attacks, hacks still happen every now and then. Once a site is hacked and you visit, it’s likely that your machine may be infected.
It’s no one’s fault – not yours or that of the site.
Nonetheless, you still get the malware.
What do I do if problems return?
After you’ve taken the malware off of your computer, my first suggestion is to watch what you’re doing.
If you aren’t doing the things that I’ve bulleted above but your browser is still being hijacked, then you want to keep a careful watch. Track which sites you visit and what you do between the time that the malware was removed and when the browser hijack reappears.
As always, the key to preventing problems like this is vigilance and good anti-malware software that’s up-to-date. Watch what you do and it’s likely that your browser won’t by hijacked by this malware anymore.