How Do You Find Malware On Your Computer?

Updated on October 1, 2026, by Xcitium

To find malware on your computer, run an updated full antivirus or malware scan and check for warning signs such as unusual slowdowns, crashes, pop-ups, browser redirects, unknown programs, disabled security software, suspicious processes, or unexpected network activity. If malware is still suspected, use an offline scan or endpoint detection tool.

Malware always finds various means to enter your system and slip into your software causing maximum damage. While surfing, clicking links, downloading or uploading your computer is vulnerable and prone to malware attack. However, if you are careful, then you might be able to avert virus attack or stay protected for a long time.

Before going to the strategies of finding malware in your computer, let me explain what is malware, what does it do? As you might be aware of malware, they are malicious programs specially designed to work in an unethical way and do all illegal things with your computer and your personal data stored on your computer.

The intentions behind the creation of malware may be to steal your private and confidential information from your computer to slow down and damage your computer. Here are some of the common malware symptoms,

Missing Files and Folder Option

Using the folder option on your Windows computer, you can configure your computer to show hidden system files and display file extension for known files. If you are not able to access those folder options or some of your system files are gone missing, malware might have disabled it.

Folders On Your External Drives Have Become Inaccessible

There are chances that the attributes of all your folders are changed to ‘system hidden’ by malware. Also, the malware might create a visible copy of itself with the same name and icon as the folder. It hides the file extension so that you can not determine whether it is a folder or file and when you open it you are actually triggering the malware instantly.

Sluggish Computer

If your computer suddenly becomes sluggish with frequent system crashes and freezes, then it is a clear sign of a malware infection. In fact, opening various software applications and windows will take too long to load or open. All these are indicative of the presence of malware in your computer.

Presence of Suspicious Files

If you find any suspicious files with unknown file extensions on your computer or in your external storage media files, it might be a sign of malware infection on your computer.

Apart from the signs mentioned above, malware can bombard your computer screen with multiple pop-ups. It can also execute applications that will transfer your files from one folder to another. Some malware can even completely wipe your data stored on the computer.

The best way to remove malware and to prevent future infection is to install a good antivirus software such as Xcitium Antivirus on your computer.

For organizations, finding and removing malware is not easy. There may be multiple legacy endpoints/devices deployed at different locations. Hence, it is extremely difficult for organizations to implement security at the granular level.

How to Find Malware on Your Computer in 8 Steps

Look for common signs of malware.
Update your antivirus or security software.
Run a full malware scan.
Check installed programs for unknown software.
Review running processes for suspicious activity.
Inspect browser extensions and settings.
Check for unusual network or account activity.
Run an offline scan if malware is still suspected.

Do not rely on symptoms alone. Slow performance or crashes can have legitimate causes, so use a reputable security scan to confirm whether malware is present.

How Can You Tell If Your Computer Has Malware?

Common malware warning signs include:

Warning Sign	What You May Notice
Slow performance	Computer suddenly takes longer to respond
Frequent crashes	Programs or the operating system freeze unexpectedly
Pop-ups	Unexpected advertisements or fake security warnings
Browser redirects	Browser opens pages you did not request
Unknown programs	Applications appear without your knowledge
Suspicious processes	Unfamiliar processes consume system resources
Disabled security	Antivirus or firewall stops working unexpectedly
Changed browser settings	Homepage or search engine changes
Missing or modified files	Files disappear or change unexpectedly
High resource usage	CPU, memory, disk, or network usage increases unexpectedly
Account alerts	Unknown logins or activity appear on your accounts
Unusual network traffic	Device communicates unexpectedly while idle

These symptoms can indicate malware, but they do not prove an infection by themselves.

Quick Scan vs. Full Scan vs. Offline Scan

Scan Type	What It Does	Best Used For
Quick Scan	Checks common threat locations	Routine checks
Full Scan	Examines a broader range of files and locations	Suspected malware
Custom Scan	Checks selected files, folders, or drives	Specific suspicious items
Offline Scan	Scans outside the normal operating environment	Persistent or hidden malware

If you suspect an active infection, start with a full scan rather than relying only on a quick scan.

How Do I Check for Malware on Windows?

On Windows, start with your installed antivirus or Windows Security.

A typical process is:

Open Windows Security.
Select Virus & threat protection.
Open the available scan options.
Select an appropriate scan.
Run the scan.
Review detected threats.
Quarantine or remove confirmed malware as recommended.
Restart the computer if required.
Scan again if suspicious behavior continues.

If malware appears to interfere with Windows or normal scanning, consider an offline scan.

Can Task Manager Detect Malware?

Task Manager can help reveal suspicious processes, but it cannot reliably determine by itself whether a process is malware.

Malware may:

Use misleading names
Imitate legitimate processes
Inject code into legitimate processes
Hide its activity
Run only at specific times

Use Task Manager together with antivirus, endpoint-security, or other trusted detection tools.

How Can I Check a Suspicious File for Malware?

If you find a suspicious file:

Do not open it.
Check where it came from.
Verify the filename and extension.
Scan it with your security software.
Check whether the publisher is known.
Quarantine it if your security software identifies it as malicious.

Do not execute a suspicious file simply to see what it does.

Security teams can analyze unknown files in controlled sandbox environments when deeper investigation is required.

What Is Malware Detection?

Malware detection is the process of identifying malicious software or suspicious behavior on a computer, endpoint, or network.

Security tools can use several detection techniques.

Detection Method	How It Works
Signature detection	Matches known malicious patterns
Heuristic detection	Identifies suspicious characteristics
Behavioral detection	Watches for malicious activity
Reputation analysis	Evaluates files using known reputation data
Sandbox analysis	Runs suspicious files in an isolated environment
Endpoint monitoring	Watches processes and endpoint activity
Network detection	Identifies suspicious communications

Modern malware detection often combines several methods rather than relying on one technique.

Can Malware Slow Down Your Computer?

Yes, malware can consume:

CPU
Memory
Disk resources
Network bandwidth

This may cause the computer to become slow or unstable.

However, a slow computer does not necessarily have malware.

Other causes include:

Too many startup applications
Limited memory
Low storage space
Hardware problems
Background updates
Resource-intensive legitimate applications

Run a security scan before assuming malware is responsible.

How Do I Know If Malware Is Completely Removed?

After remediation:

Run another full scan.
Consider an offline scan for persistent threats.
Verify that security software remains enabled.
Check that redirects and pop-ups have stopped.
Review suspicious applications and extensions.
Monitor accounts for unauthorized activity.
Confirm that unusual processes do not return.

For a serious compromise, the safest response may involve rebuilding the computer from a trusted image rather than trying to prove manually that every malicious component is gone.

Signs of Malware vs. Other Computer Problems

Symptom	Could Be Malware	Could Also Be
Slow computer	Yes	Low memory, old hardware
Crashes	Yes	Driver or hardware problems
Pop-ups	Yes	Website notifications
High CPU usage	Yes	Legitimate applications
Browser redirects	Yes	Bad extension or settings
Missing files	Yes	User error or disk problems
Network activity	Yes	Cloud sync or updates
Low storage	Yes	Large legitimate files

Xcitium Advanced Endpoint Protection (AEP) is an ideal solution for such scenarios as it offers all-around protection across devices and OS platforms. With built-in containment engine and ‘Default Deny’ platform, Xcitium AEP provides complete protection against any malware threat including zero-day malware.

For more details about Xcitium Advanced Endpoint Protection, contact us at +1 888-256-2608.

Frequently Asked Questions

How do you find malware on your computer?

Run an updated full security scan and check for suspicious programs, processes, browser changes, pop-ups, redirects, and unusual system behavior.

What are the first signs of malware?

Common signs include slow performance, crashes, pop-ups, browser redirects, unknown applications, and disabled security software.

Can malware hide on a computer?

Yes. Some malware is designed to operate quietly and evade detection.

Can Task Manager show malware?

It can reveal suspicious processes, but Task Manager alone cannot reliably identify malware.

Can Windows Security detect malware?

Yes. Microsoft Defender Antivirus can detect many types of malware on supported Windows systems.

Should I run a full malware scan?

Yes, especially when you suspect an infection or unexplained suspicious behavior.

What if the malware scan finds nothing?

Update your security software, consider an offline scan, and investigate persistent suspicious activity.

Are pop-ups always malware?

No. Pop-ups may come from websites or notification permissions, although malware and adware can also cause them.

Does a slow computer mean malware?

Not necessarily. Hardware, storage, applications, and updates can also cause slow performance.

What should I do if malware is detected?

Quarantine the threat, rescan the computer, update software, and protect potentially exposed accounts.