How to Get Rid of Malware on a PC: A Practical, Step-by-Step Guide

Has your PC suddenly become slow, flooded with pop-ups, or acting “weird” even when you’re not doing anything? If you’re dealing with unexpected crashes, unknown programs, or browser redirects, there’s a good chance malware is involved.

Malware isn’t just a personal inconvenience anymore—it’s a global business risk. A single infected device can become an entry point for credential theft, ransomware, and data leaks. Whether you’re an IT manager handling endpoints at scale, a founder protecting customer trust, or a security-conscious professional, knowing how to get rid of malware on a PC quickly and correctly can save time, money, and reputation.

This guide explains exactly how to remove malware from a computer, how to confirm it’s gone, and how to prevent it from coming back—without unnecessary jargon.

What Is Malware (and Why It’s So Hard to Remove)?

Malware is any software designed to harm, disrupt, spy on, or gain unauthorized access to your system. It includes:

• Viruses (infect files and spread)

• Trojans (masquerade as legitimate apps)

• Spyware (steal data, track activity)

• Adware (aggressive ads, redirects)

• Keyloggers (capture keystrokes, passwords)

• Ransomware (encrypts data for payment)

• Rootkits (hide deep in the OS)

Modern malware is often built to resist removal. Some variants disable security tools, create scheduled tasks, modify browser policies, or reinfect the system through hidden startup entries.

That’s why simply “deleting a suspicious file” doesn’t always work. You need a reliable process to clean malware thoroughly.

Common Signs Your PC Has Malware

Before jumping into fixes, confirm the symptoms. Malware is likely if you notice:

• Frequent pop-ups or fake antivirus alerts

• Browser redirects to unknown sites

• New toolbars/extensions you didn’t install

• High CPU usage when idle

• Antivirus disabled or won’t update

• Unknown programs installed

• Slow startup and constant disk activity

• “Your files are encrypted” or ransom notes

• Emails/messages sent from your accounts without you

If you’re thinking “how do I remove malware?” the answer starts with isolation and diagnosis.

Step 1: Disconnect and Contain the Infection

Before you try to remove anything:

1. Disconnect from the internet (Wi-Fi/Ethernet)

   • This helps stop data exfiltration and prevents malware from downloading more components.

2. If this is a work device, inform IT/security immediately.

3. Do not plug in external drives until cleanup is complete (malware can spread).

For businesses, isolation matters because one compromised machine can threaten the whole network.

Step 2: Back Up the Right Way (Without Carrying Malware)

You should back up essential documents—but carefully:

• Only back up personal/work files (documents, photos, spreadsheets)

• Avoid copying executable files (.exe, .bat, .scr, unknown installers)

• Do not copy “Program Files” folders

• If possible, back up to a cloud service with version history

If you suspect ransomware, do not modify encrypted files. Preserve them for recovery options.

Step 3: Boot into Safe Mode (Recommended)

Safe Mode loads Windows with minimal drivers and startup apps, making malware easier to remove.

Windows 10/11 Safe Mode:

1. Press Windows + I → Update & Security

2. Go to Recovery → Advanced Startup → Restart

3. Select Troubleshoot → Advanced options → Startup Settings

4. Restart and choose Safe Mode with Networking (only if you need downloads)

If your device is heavily infected, use Safe Mode without networking and transfer tools via a clean USB.

Step 4: Run a Full Malware Scan (Start With Built-in Tools)

Use Microsoft Defender (Windows Security)

Even if you use another antivirus, Defender is a solid baseline.

1. Open Windows Security

2. Go to Virus & threat protection

3. Run:

   • Quick Scan

   • Then Full Scan

   • Finally, Microsoft Defender Offline scan (best for stubborn threats)

Offline scan restarts the PC and checks malware before Windows fully loads—useful for rootkits and persistent infections.

This is often enough to get malware off your computer when the infection is common.

Step 5: Use a Second Opinion Scanner (For Better Coverage)

If you want to completely remove malware from PC, a second scanner often catches what the first one misses. Many professionals use additional tools because malware families behave differently.

Best practice:

• Use a reputable malware remover (secondary scanner)

• Update it before scanning

• Run a full system scan

• Quarantine and remove threats

Avoid random “free malware cleanup” tools from unknown sites. Ironically, many are malware.

Step 6: Remove Suspicious Programs and Browser Hijackers Manually

Even after scans, you may need to clean up leftover adware or unwanted programs.

Uninstall suspicious apps

1. Go to Control Panel → Programs → Uninstall a program

2. Sort by date installed

3. Remove unfamiliar or unwanted apps (especially toolbars, “PC cleaners,” unknown PDF tools)

If you’re asking “how to uninstall malware,” this is one of the most overlooked steps.

Reset browser settings (Chrome/Edge/Firefox)

Malware often modifies:

• Homepage

• Default search engine

• Extensions

• Proxy settings

Chrome/Edge:
Settings → Reset settings → “Restore settings to their original defaults”

Also:

• Remove suspicious extensions

• Clear browser cache/cookies

• Disable notifications from unknown websites

Step 7: Check Startup Items, Scheduled Tasks, and Services

Persistent malware reappears because it’s configured to start automatically.

Check Startup Apps

• Press Ctrl + Shift + Esc → Task Manager → Startup

• Disable anything suspicious

Check Scheduled Tasks

• Search Task Scheduler

• Review Task Scheduler Library

• Look for unfamiliar tasks running scripts, PowerShell, or random file paths

Check Services

• Run services.msc

• Look for unusual services with generic names, no publisher, or odd descriptions

This is essential if you’re trying to delete malware that keeps returning.

Step 8: Clean Temporary Files and Remove Hidden Junk

Use Windows built-in cleanup to remove temp files malware sometimes uses.

• Settings → System → Storage → Temporary files

• Or run cleanmgr

This helps reduce scan time and removes hidden installers.

Step 9: Update Windows and All Software Immediately

Outdated systems are the #1 reason infections happen again.

Update:

• Windows Update

• Browsers

• Java (if you must use it)

• Adobe apps

• Office apps

• VPN/remote tools

• Endpoint security agent

If you don’t patch, you might remove malware today and get reinfected tomorrow through the same vulnerability.

Step 10: Change Passwords (From a Clean Device)

If malware included a keylogger or credential stealer, your passwords may already be compromised.

From a clean device:

• Change email password first

• Change banking and admin passwords

• Rotate business credentials

• Enable Multi-Factor Authentication (MFA)

For businesses, enforce:

• Password managers

• MFA for cloud apps

• Conditional access policies

This is crucial even if you believe you’ve learned how can I delete malware successfully.

Step 11: Verify the System Is Clean

To confirm your PC is safe:

• Run a second full scan after reboot

• Monitor CPU usage in Task Manager

• Confirm no unknown startup items return

• Check browser search engine remains unchanged

• Review network usage (no unusual spikes)

• Confirm Windows Security is enabled and updating

If suspicious behavior continues, malware may be deeper than expected.

When You Should Reinstall Windows (The “Guaranteed Clean” Option)

Sometimes, the safest answer to “how to remove malicious malware from PC” is a clean OS reinstall.

Consider reinstalling your OS if:

• You suspect a rootkit

• Defender and secondary scanners can’t clean it

• You’re seeing repeated reinfections

• You handle sensitive business data

• You’ve had credential theft or ransomware

A clean reinstall eliminates persistence mechanisms—but make sure you:

• Back up only safe files

• Reinstall apps from official sources

• Reset router and Wi-Fi passwords if necessary

For executive leadership and IT teams, a reinstall may cost time but reduces long-term risk.

How to Prevent Malware From Coming Back

Prevention is cheaper than cleanup. Here’s how to protect your environment:

Personal/Professional Users

• Keep Windows and software updated

• Use strong antivirus/endpoint protection

• Avoid pirated software and unknown downloads

• Disable macros unless absolutely needed

• Use a password manager + MFA

• Use standard user accounts for daily work (not admin)

Businesses / IT Managers / Founders

• Implement EDR or endpoint security across all endpoints

• Use email filtering and anti-phishing training

• Enforce least privilege and role-based access

• Patch management policy

• Backups with offline or immutable storage

• Incident response plan and logging

If malware reaches one endpoint, your prevention strategy determines whether it becomes a company-wide event.

Quick Checklist: How to Clean PC From Malware

If you want a fast summary:

1. Disconnect from internet

2. Boot into Safe Mode

3. Run Microsoft Defender full scan + Offline scan

4. Run a second scanner

5. Uninstall suspicious apps

6. Reset browser + remove extensions

7. Check startup apps and scheduled tasks

8. Clear temp files

9. Update Windows and software

10. Change passwords from a clean device

11. Confirm clean behavior after reboot

1) How do I know if malware is completely removed?

Run a full scan with your primary antivirus and a second scanner after reboot. Confirm no suspicious startup entries return, and check browser settings don’t revert.

2) Can I delete malware by just removing a file?

Sometimes, but many threats have persistence mechanisms (startup entries, scheduled tasks, registry changes). File deletion alone often fails and can even break the system.

3) How can I get rid of malware without losing my files?

In many cases, Safe Mode + full scans + removing malicious apps/extensions works. However, if you suspect ransomware, credential theft, or a rootkit, a clean reinstall is safer.

4) How do I remove malware from Windows 10 specifically?

Use Windows Security (Defender) full scan and the Defender Offline scan, then remove suspicious apps, reset browsers, and check startup/scheduled tasks.

5) What if malware keeps coming back after removal?

That usually means:

• a scheduled task or startup item is restoring it

• a browser policy or extension is forcing redirects

• a hidden dropper is still present

• your device is being reinfected from the same source (email, USB, vulnerable software)

At that point, consider a professional cleanup or a full reinstall.

Final Thoughts (And Why This Matters)

Malware is no longer just a consumer issue. It is one of the fastest paths to ransomware, data breaches, and financial fraud. If you’re responsible for business operations, client trust, or IT security, it’s essential to treat malware cleanup like a process—not a quick fix.

If you want expert help identifying what infected your PC, removing it safely, and preventing reinfection, reach out here:

Contact support: https://scanoncomputer.com/contact/