How to Determine If Your Computer is Infected by a Virus

Key Takeaways

To ensure your PC is virus-free, it is recommended to perform a manual virus scan using reliable antivirus software such as Microsoft Defender, Malwarebytes, or another trusted program. Alternatively, you can press Ctrl+Shift+Esc to open the Task Manager and identify any unusual processes consuming excessive system resources.

Not every sluggish or malfunctioning Windows computer is a victim of malware. However, it is possible for these systems to get viruses and other forms of malware. To determine if your PC is infected and if a particular suspicious process is posing a risk, follow the steps below. This article is presented by Incogni in partnership with Cybersecurity Awareness Week.

What Are the Signs of a Virus?

Instances of subpar performance, application failures, and computer freezing may occasionally indicate the presence of a virus or other malicious software causing havoc. Yet, this is not always the scenario as there exist numerous other factors that can impede your computer's efficiency.

Similarly, the fact that your PC is functioning properly does not guarantee that it is free of malware. In the past, viruses were often seen as harmless pranks that consumed a significant amount of system resources. However, contemporary malware tends to operate silently and covertly in the background, attempting to avoid detection in order to obtain sensitive personal information, such as credit card numbers. Essentially, modern-day malware is primarily designed by criminals with the intention of making money, and well-crafted malware will not cause any noticeable issues with your PC.

Nevertheless, experiencing sudden and significant declines in PC performance may indicate the presence of malware. Additionally, the presence of unfamiliar applications on your system could be a sign of malware. However, it is important to bear in mind that the existence of these indicators does not guarantee the involvement of malware. Some legitimate software may display a Command Prompt window during updates, so if you observe strange windows quickly appearing and disappearing, it may simply be a normal part of the software on your system.

How to Check if a Process Is a Virus or Not

Determining the presence of malware on your PC cannot be based on a universal indicator; a thorough scan is imperative. Malware can manifest as PC issues or operate inconspicuously while achieving its objective surreptitiously. To ascertain if your system is infected, diligent investigation is required.

You may be concerned about a potential computer virus if you have noticed an unfamiliar process in the Windows Task Manager. To access the Task Manager, you can either press Ctrl+Shift+Esc or right-click the Windows taskbar and choose "Task Manager."

Here you'll find a number of processes, and if you see a shorter list, you can click "More Details." The names of these processes may appear unusual and perplexing, but that's to be expected. Windows incorporates numerous background processes, your PC manufacturer includes some as well, and additional ones are often added by the applications you install.

Malicious malware often exhibits high usage of CPU, memory, or disk resources, making it easily noticeable. To determine if a particular program is malicious, right-click on it in the Task Manager and choose "Search Online" for detailed information.

If the search results indicate that the program is associated with malware, it is highly likely that your system is infected. However, do not assume that your computer is free from viruses solely based on the appearance of a legitimate-looking process. It is possible for a process to deceive by posing as "Google Chrome" or "chrome.exe," when in fact it is malware disguised as Google Chrome located in a different directory on your system.

Another useful tool is VirusTotal, which enables you to scan a file using various antivirus brands concurrently, providing a comprehensive analysis of whether it contains malware or not. In this instance, we will scan the executable of the process. To locate the process's executable, simply right-click the process in Task Manage and choose "Open File Location."

Note the address and executable name in File Explorer.

Now you have two choices: either click on "Choose File" and browse to the location of the exec file using the file path you had previously recorded, or simply drag and drop the EXE file from the File Explorer onto the VirusTotal page.

It'll take a moment to analyze it (and larger files do take longer), then it'll show you the results from each antivirus suite.

Clicking on the other tabs will provide you with more detailed information or allow you to join the community discussion about the subject.

If you suspect that your device is infected with malware, we highly recommend conducting an anti-malware scan.

How to Scan Your Computer for Viruses

The integrated Windows Security application, also known as Microsoft Defender, automatically scans your PC for malware by default in Windows 11. Nevertheless, you have the option to manually initiate scans.

Open your Start menu on Windows 10 or 11, and search for "Security." Then, click on the "Windows Security" shortcut to open it. Alternatively, you can navigate to Settings > Update & Security > Windows Security and select "Open Windows Security" on Windows 10. On Windows 11, go to Settings > Privacy and Security > Windows Security and choose "Open Windows Security."

To perform an anti-malware scan, click "Virus & threat protection."

Perform a malware scan on your system by clicking on "Quick Scan." Microsoft Defender will carry out the scan and provide you with the results. In case any malware is detected, it will offer to automatically remove it from your PC.

If you suspect that your computer may be infected with malware and your primary antivirus software fails to detect anything, it is always advisable to seek a second opinion. One way to do this is by conducting a scan using an alternative security application.

We highly recommend using Malwarebytes in conjunction with Windows Security for an additional level of PC protection. The free version of Malwarebytes allows you to manually scan your computer for viruses and other types of malware. If your intention is solely to test for malware, the free version will suffice. The paid version offers real-time protection as well.

If your antivirus software detects malware but is unable to remove it, we suggest trying the following methods: conducting a scan in Safe Mode, utilizing antivirus rescue software, or employing Microsoft Defender's Offline Scan.

You can also ensure you don't have malware on your PC by resetting Windows to its default state.