One question that shows up almost every day in the Ask Leo! inbox is how to remove malware.
Every day.
The scenarios may be different, but the problem is the same: a machine has been infected with spyware, a virus, or some other form of malware and that machine’s owner is having a tough time getting rid of it.
And it often happens with anti-malware software installed that “should” have taken care of it before it got to this stage.
Hopefully, that’ll never be you. If it is, let’s review the steps that I recommend for removing malware and reducing the chances that it’ll happen again.
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A word about prevention
If there’s only one thing that I would have you take away from this article, it would be this:
Prevention is much less painful than the cure.
As we’ll see in a moment, the steps that may be required to remove malware can be painful and time consuming. While it sometimes might seem like work, keeping your machine and anti-malware software up-to-date, following internet “common sense,” and knowing how to stay safe on the internet is much, much easier in comparison.
So, let’s look at what to do when prevention has failed.
Backup
My strong recommendation is that you start by taking a complete image backup of your system.
Why would you want to backup a system that you know is infected with malware?
Because this backup is an “it-can’t-get-any-worse-than-this” fallback. Some of the techniques that we might use to remove malware can actually break things and make the situation worse instead of better. With this backup at the ready, you can always restore and start over with nothing lost.
Restore a prior backup
If you’ve been taking regular backups, this is often the most expedient step and can save a lot of time and energy.
Simply restore your machine completely from the most recent full system backup, plus any incremental backups, taken before the infection occurred. You can then carefully restore any late-changing data from the backup you took.
And, except for learning from the experience, you’d be done.
Unfortunately, most people don’t have this option available to them. Most people don’t begin backing up until after they’ve experienced data loss or a severe malware infection. One of the lessons they learn is that a recent backup is something that can save them from almost any problem – including malware.
Update the anti-malware database
If you have anti-malware software installed, make sure that it’s up-to-date. I’m talking about more than just the software itself, but the database of malware definitions.
Almost all anti-malware tools use databases of malware definitions, which needs to be updated regularly. New malware is constantly appearing, and as a result, that database of definitions needs to updated often – at least daily.
Many programs will do this automatically, but if for some reason they do not, then the programs will not ”know” about newer malware. Make sure that the database is up-to-date so that yours does.
Perform a full scan
Quite often, anti-malware tools will regularly perform a “quick” or fast scan. That’s typically quite sufficient for day-to-day operations.
But not today.
Fire up your anti-malware tools and run a full/advanced/complete scan of your entire system drive – typically the C: drive. If you have a single tool, that might be one run; if you use multiple tools, such as separate anti-virus and anti-spyware tools, then run a full scan with each. This may take some time, but let the tools do their job.
This also covers if your anti-malware tools automated scans have stopped for some reason. If this full scan discovers something, it might be worth checking to make sure that the security software is properly configured to scan automatically as well.
Try another anti-malware tool
No anti-malware tool catches all malware.
I’ll say it again: there is no single tool that will catch every single piece of malware out there. None. Some are better than others, some catch more than others, but none of them catch everything.
So as you might expect, trying additional reputable tools is a reasonable approach.
I recommend the free version of Malwarebytes’ Anti-Malware as the first tool to use. It has a reputation for removing some nasties that other tools apparently miss. Once again, run a full scan.
Regardless of which tool you select, I have to stress: stick with reputable tools. When a machine is infected, most people tend to panic and download just about anything that claims to be an anti-malware tool. Don’t do that. There are many less-than-reputable individuals out there ready to take advantage of your panic.
Do some research before downloading anything or you may well just make the problem worse instead of better.
Research specific removal instructions
If your anti-malware software tells you the name of the specific malware you’re dealing with, that’s good information even if it can’t remove it.
Search for that malware and you’re likely to find specific removal instructions at one or more of the major anti-malware vendor sites. These instructions can often be somewhat technical and intimidating, so take your time to follow them precisely or get a techie friend to help.
They’ll also often come with recommendations that indicate that the vendor’s software will remove the malware – for a price. As long as it’s an option (in other words, the manual removal instructions are provided), then it may be a viable alternative if the company is one you trust. On the other hand, if all you’re presented with is a promise and a price, I’d move on.
Some sites offer free tools that you can download to remove specific malware. Once again, use caution. When the tools are from reputable sources, they’re a quick way to avoid some hassle. When the tools are really just more malware in disguise, they’ll only make your problems worse.
If you download anything to help address the problem, make sure that wherever it is comes from, it’s an organization that you know and trust.
Surrender
This is the only sure-fire way to remove any virus. 100%. Guaranteed.
In fact, it’s the only way to know that you’ve removed a virus. Once infected, none of the steps above, aside from restoring to a backup taken before the infection, are guaranteed to remove the malware, even if they report that things are clean. Once infected, all bets are off. An infection could fool anti-malware software into thinking that everything is fine even when it’s not.
There’s just no way to know.
The only way to be absolutely positive that you’ve removed any and all viruses is:
- Back up: If you haven’t already, back up the entire system. You’ll use this to restore your data after we’re done.
- Reformat: Reformatting erases the entire hard disk of everything: the operating system, your programs, your data, and most important of all, any and all viruses and malware. This may be part of the next step as most Windows setup programs offer to reformat the target hard drive before installing Windows.
- Reinstall: Yes, reinstall everything from scratch. Reinstall the operating system from your original installation media. (Or restore the system to an image backup you took when you got the machine to preserve the “factory original” state.) Reinstall applications from their original media or saved downloads.
- Update: Update everything in particular making sure to bring Windows as completely up-to-date as possible for the most current protections against all known and patched vulnerabilities. Applications and particularly your anti-malware tools should be updated as well.
- Restore: Restore your data by carefully copying it back from the backups you created when we started. By “carefully,” I mean taking care to only copy what you need, so as not to copy back the malware.
- Learn: Take stock of how this happened, what you might have done to get infected in the first place, and what might have helped you recover more efficiently. Consider instituting a frequent system backup.
It’s not your fault (but it is your responsibility)
By now, I hope you can see why prevention is so much less painful than the cure.
Taking a few extra steps to keep things up-to-date, avoiding those cute virus-laden downloads and attachments, and just generally learning how to stay safe is much easier than the recovery process that I’ve just outlined.
And having backups can make the recovery process as close to painless as possible if you do get infected.
Yes, it’s not your fault, but it is your responsibility to do the basics to stay safe when you use your computer
In an ideal world, we’d never have to worry about malware or the “bad guys” trying to fool us into doing things we really shouldn’t. But you already know that this isn’t an ideal world; software isn’t perfect and never will be. There will always be someone out to scam the vulnerable.
Even though it’s not your fault, you still need to be the one to get educated and take the steps needed to stay safe.
Right or wrong, it’s just a practical reality.
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The free version of Malwarebytes is very good – I’ve never used the paid-for version and have successfully cleared all sorts of problems for clients.
The reformat has one tricky part — If the virus gets into the boot sector, a quick format usually won’t dislodge it.
For that, you have to zero out the drive — using DBAN or something similar.
Malwarebytes is in fact free, and a GREAT removal program. The only things extra you get from the payed version is, real-time protection, and automatic updates. But the free version, you can just easily hit the Update button to get all the definitions, and use the On-Demand scans.
-Mike
Good article, but surprised you didnt mention rolling back your XP/Vista to a system restore point before the date you noticed the pop up, its worked for me, and a lot easier task for most people than full system restore.
22-Jul-2009
I had a very bad piece of spyware/malware on my computer and went to Microsoft security update and downloaded the OneCare software online. Yep! This did the trick. It killed it. Thank you, Microsoft.
The only way to truly get rid of a virus is to fully reformat the machine. I keep all my data on an external drive, and anything that I download is on my main drive first. That way, my data is never affected. Backup of course anyway though.
There is another approach, one that is more reliable than using anti-malware software from inside the infected OS and less drastic than a total re-format -> scan for malware from outside the infected OS, without actually running the infected OS. I wrote a trio of articles on this which are summarized here:
Removing malware is best done from the outside
http://blogs.computerworld.com/removing_malware_is_best_done_from_the_outside
For the most terrible malware I have found that ComboFix does a great job.
HOW DO I REMOVE UPDATER.EXE? I TRIED USING TASK MANAGER, DIDN’T WORK. I TRIED USING MALWAREBYTES, NO GOOD.
Best way is to remove hard drive, put in different computer and run anti-virus on it.
I have updated my antivirus and then run that in safe mode,it worked and killed it.Kasper sky works on malware too.
MY external hard drive; can it be infected too? will moving material back and forth re-infect the re-programmed computer?
div class=”leocomment”>It is possible, yes. Some malware can, and does, spread through external and portable drives.
18-Nov-2009
The only way to remove a virus fully is to format your hardrive
13-Jan-2010
First, I would run my anti-virus program, then choose the “check for updates” to make sure that it is, then choose “complete system scan” or “full system scan” to see if it finds anything. Then try a adware scanner. Ad-Aware has a pretty good one you can use manually for free. You do have to buy it if you want continuous automatic protection.
Reformatting and reinstalling often works out quicker in the long run and gives a very satisfying feeling of victory..
The only weakness is any reinstalling data ..only do this for critical stuff otherwise you have a higher risk of reinfection.
Jp
I have a virus that won’t allow me to do anything on the computer anymore, once it is up and running. How do I get to the point of reformatting and reinstalling. Don’t I need a boot disk or something?
Good article Leo, very informative. From this article can you please tell me in more detail the steps I need to take from “The only way to be absolutely positive that you’ve removed any and all viruses is: backing up the computer down to restoring the data.” I need a step by step explanation about how to do that. cheers.
A few months ago I got an Antivirus Program pop-up and it took over my computer completely. Every single program I clicked on said it had a trojan. It recommended that I purchase their antivirus program to remove the virus (they installed!). They even sent an official-looking Microsoft screen that recommended I buy their program. After 5 hours of trial, error and tears, the easy solution was to reboot in Safe Mode and then choose “no” at one point so I could to go to System Restore while in Safe Mode. I then selected the first date and time (yesterday) when I didn’t have this infection to restore my computer to. I let the computer do it’s restoration and it automatically rebooted, and my computer was clean and working perfectly again. SAFE – EASY – EFFECTIVE SOLUTION! It’s been fine for months now. I hope this helps others.
Forgot situations that you get your bios flashed.:) There is viruses that infect bios too.:) You can’t reformat the drive for those.
The guy in the computer shop said BIOS virus infections are very rare because not many folk use floppy disks anymore.This is where most of them used to be introduced many years ago ..as I recall.
Jp
i am a XP user .but recently i am effacted a virus.i have allready avira its allready updated.but it cant do nothing.the did in my pc like that:- i am working but suddenly everything is close and i dont get time to save.and whan i on task manager i got JIBANU.exe.what can i do
When viri disable the Task Manager and don’t allow using RegEdit, I have often had success using a third party registry editor. However, occasionally, a virus may monitor the Registry value and set it right back to disable the T M right after you change it.
Leo,
You say:
“The only way to be absolutely positive that you’ve removed any and all viruses is:
* Backup [...]
* Reformat [...]
* Reinstall everything, from scratch [...]
* Update everything [...]“
Fine … … were it not for the following:
“
* Restore your data by carefully copying it back from the backups you created. By “carefully” I mean taking care to only copy what you need, so as not to copy back the virus.“
This is the catch.
For how could one possibly “only copy what you need, so as not to copy back the virus” ???!!!
Malware could lurk inside a data file that appears legitimate. How do I know that it is not hiding inside any one among hundreds of those nice photo images that I had downloaded over the web long time ago? … …
Johan
31-Dec-2010
Also using Linux, a live cd, ClamAv. Am visually impaired, and one of my brothers machines has the FBI ransomware malware on it and honestly, who knows what else, so safe mode isn’t an option. So, Linux to the rescue
Most likely, Ubuntu, or GRML since I know the screen reader is built in. That’s another way of removing.
Prevention is much less painful than the cure .
thanks. good advice.
After a major collapse of my system caused by an electrical storm I have had to re-install 3 times from my LEGAL Windows XP CD. The first time I realised that the disc had been corrupted even though it was the first time since new (over 6 years ago) that it had been used. On that occasion I was able to download SP3 quite simply and not in ISO form – don’t ask me how but I am sure it was from MS. However, the first re-install was hopeless and it has taken two more re-installs to get an almost perfect situation with just the odd cursor freeze, shutdown failure and one or two different BIOS booting requirements – it seems to change its mind whether it wants F8, enable boot login, etc., etc. Still, that is a small price to pay for hours and hours without stalling or shutting down.
The main problem is that it is impossible to get Windows Automatic Updates from a 2000 System with only SP2 installed. Also, MS now will only download SP3 by ISO. Every form of WINrar, etc., all require a more updated Windows before helping me. I was able to burn the SP3 vide Nero to a disc but, because of Window’s intransigence, it cannot be read to my hard drive yet.
I am shown as receiving Windows Updates according to my settings but nothing arrives at 3am. Their literature states that SP3 will be received by me automatically – SOME CHANCE !! The only Windows
update I have received crashed my computer the moment I reached the Welcome screen.
I have seen many people complaining that they cannot get Windows to install after a re-install – please someone tell me what is going on I am pretty certain that I do not have a virus or trojan aboard.
I happily use the “paid” version of Malwarebytes. Worth the money!
Since becoming a convertee to Sandboxie, I & friends have not had malware infections .
I often browsethe web in and unsafe manner and open all email attachments without fear .
Providing data is NOT saved out side the protective Sandbox, your computer will be protected …. Look up Youtube vids for more info and initial settings which can sometimes be tricky for the newbie. Sandboxie is free but a 5 second nag screen will appear after 1 month ..no big deal though, just click and it goes away.
http://www.sandboxie.com/
I use Malware Bytes ( paid version). But I boot to the “C” prompt when window do not solve problem. I go into the directory and run Malware Bytes from there, you and also run C Cleaner, AVG, and the majority of Anti Virus programs will run from the “C” prompt, but you have to go into that directory to run the executable file.