Trojan.multi.certstor.a Virus Removal (March 2019 Update)

This page aims to help you remove Trojan.multi.certstor.a Virus. Our removal instructions work for every version of Windows.

The malicious infections inflicted by the viruses known as Trojans are extremely dangerous and cunning. Such infections normally go unnoticed and the user realizes what has been going on after the virus has completed its mission. The kind of malware we are talking about here is exactly a version of the Trojan Horse malware category – to be more precise, its name is Trojan.multi.certstor.a.

Why is Trojan.multi.certstor.a identified as a Trojan?

Trojan.multi.certstor.a is an example of a typical Trojan horse version. It invades your device with neither your knowledge nor your permission. Later, it might have many purposes but it remains out of the sight until it has finally achieved its purpose. This is the reason why this kind of malware has been named after the Greek horse that deceived the Trojans into thinking it was a harmless gift. Following that, when no one was suspicious and cautious, the horse finally revealed its true nature and decided the outcome of the war. Lots of the infiltrated devices’ owners have no idea about the contamination before it is already too late to do anything.

How do Trojans get around?

Trojan.multi.certstor.a, as a normal Trojan version, could get around in a lot of different ways. For instance, it may come as a drive-by download from a malicious web page. It could also come with a kind of Ransomware from a letter inside your email or any of its attachments – .exe files, archives, photos and documents. The virus may get distributed via torrents or shareware. At times it may be included in free software that you download from the web. Actually, there are countless opportunities for such malware to infect a computer.

What could such a virus be used for?

Normally, the way the virus is used depends on what the hackers are after as they could utilize Trojan.multi.certstor.a in different ways. In the text below we have explained the most common usages.


Trojan.multi.certstor.a Virus Removal



Some of the steps will likely require you to exit the page. Bookmark it for later reference.

Reboot in Safe Mode (use this guide if you don’t know how to do it).



Press CTRL + SHIFT + ESC at the same time and go to the Processes Tab. Try to determine which processes are dangerous. 


Right click on each of them and select Open File Location. Then scan the files with our free online virus scanner:

Drag and Drop Files Here to Scan
Maximum file size: 128MB.

This scanner is free and will always remain free for our website's users. You can find its full-page version at:

Scan Results

Virus Scanner Result

After you open their folder, end the processes that are infected, then delete their folders. 

Note: If you are sure something is part of the infection – delete it, even if the scanner doesn’t flag it. No anti-virus program can detect all infections. 


Hold together the Start Key and R. Type appwiz.cpl –> OK.


You are now in the Control Panel. Look for suspicious entries. Uninstall it/them. If you see a screen like this when you click Uninstall, choose NO:



Type msconfig in the search field and hit enter. A window will pop-up:


Startup —> Uncheck entries that have “Unknown” as Manufacturer or otherwise look suspicious.

  • Remember this step – if you have reason to believe a bigger threat (like ransomware) is on your PC, check everything here.

Hold the Start Key and R –  copy + paste the following and click OK:

notepad %windir%/system32/Drivers/etc/hosts

A new file will open. If you are hacked, there will be a bunch of other IPs connected to you at the bottom. Look at the image below:

hosts_opt (1)

If there are suspicious IPs below “Localhost” – write to us in the comments.


Type Regedit in the windows search field and press Enter.

Once inside, press CTRL and F together and type the virus’s Name. Right click and delete any entries you find with a similar name. If they don’t show up this way, go manually to these directories and delete/uninstall them:

  • HKEY_CURRENT_USER—-Software—–Random Directory. It could be any one of them – ask us if you can’t discern which ones are malicious.
    HKEY_CURRENT_USER—-Software—Microsoft—-Windows—CurrentVersion—Run– Random
    HKEY_CURRENT_USER—-Software—Microsoft—Internet Explorer—-Main—- Random

We would like you to keep in mind that these are not the only possibilities and there might be many more:

  • Data modification (sometimes even destruction) – this sort of malware might be exploited for the sole purpose of modifying or deleting data from your device.;
  • Helping Ransomware versions get spread – Trojan.multi.certstor.a may be employed in the distribution of other viruses such as Ransomware. In such a case this Trojan may find a way to sneak the other malware program in and allow carry out its illegal task. As soon as you get infected by a Ransomware virus, you should expect file encryption and ransom blackmailing. Such a file-encoding program is really hard to remove and its consequences seem to be very difficult to reverse.;
  • System crash – such a virus may be after your entire system and be set on completely crashing it. Oftentimes the user might not even be able to boot their machine into Windows.
  • Exploitation of PC resources – such malware could be programmed to turn your machine into a bot and let its creators use it as a spam distributing tool.
  • Installation of malware – this virus may serve as a malware-installation tool and you could end up infected by many other viruses due to its activities on your PC.
  • Identity theft – Trojan.multi.certstor.a may also serve as a data thief. It could be pre-programmed to copy and send all your private details and credentials to its evil makers. That way they can get access to all your accounts and private info which could have severe repercussions on your real life.
  • A means of committing cybercrimes – your PC could be turned into a tool for the cyber-criminals to do something illegal. In such a case everything happens on your behalf and as a result- you might end up prosecuted for crimes you have NEVER taken part in..

How you could remove such a contamination:

Trojan.multi.certstor.a may be counteracted by closely following the instructions inside our Removal Guide. They should allow you to take care of this noxious malware infection. In some rare situations, though, the assistance of a professional may be needed, yet we hope your case is not that complicated.

How you can prevent your PC from catching Trojan.multi.certstor.a again:

The wisest thing you can do is ignore all potential sources of Trojans. You already know all about the seriously dangerous possible effects that may come as a result of this malware’s activities on your PC. Simply avoid the possible source and the trouble coming with them. What’s more, it is crucial that you install, buy a license of and always update a top-notch anti-virus program with many capabilities of stopping and fighting various viruses.


Name Trojan.multi.certstor.a
Type Trojan
Danger Level High (Trojans are often used as a backdoor for Ransomware)
Symptoms Nothing to worry about in the beginning- the nightmare begins later when the virus unleashes its power.
Distribution Method Via all sorts of spam, malvertising and fake pop-ups.
Detection Tool

Keep in mind, SpyHunter’s malware detection tool is free. To remove the infection, you’ll need to purchase the full version.
More information about SpyHunter and steps to uninstall.

If the guide doesn’t help, download the anti-virus program we recommended or try our free online virus scanner. Also, you can always ask us in the comments for help!

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