How to Check Whether Your Windows PC Is Secure: A Beginner’s Checklist

 

Keeping a Windows PC secure does not require you to be a cybersecurity expert.

Windows already includes several built-in security features, but simply having them available does not mean you should ignore your computer's security status.

A few basic checks can help you confirm that important protections are enabled, Windows is updated, suspicious activity has not been detected, and your files and accounts are better protected.

This beginner-friendly checklist explains how to review the most important security areas on a Windows PC and what to do if something does not look right.

1. Open Windows Security First

The easiest place to begin is the Windows Security app.

To open it:

1. Click Start
2. Search for Windows Security
3. Open the app

Windows Security brings several important protection areas together in one place.

Depending on your Windows version and device, you may see areas such as:

• Virus & threat protection
• Account protection
• Firewall & network protection
• App & browser control
• Device security
• Device performance & health

Look for warnings or areas that require attention.

A green status indicator is generally reassuring, but you should still review the individual security areas periodically.

2. Check Virus & Threat Protection

Open Virus & threat protection.

This area shows information about your antivirus protection.

On a typical Windows PC using Microsoft's built-in protection, Microsoft Defender Antivirus provides real-time malware protection.

Check whether Windows reports any current threats or actions that require attention.

You should not ignore red or yellow security warnings.

If Windows reports that an important protection feature is disabled, investigate why before continuing normal computer use.

3. Make Sure Real-Time Protection Is Enabled

Real-time antivirus protection is one of the most important basic protections on a Windows PC.

It monitors files and programs while you use the computer.

This can help detect malicious software before or while it runs.

If Microsoft Defender Antivirus is your active antivirus, check that its real-time protection is enabled.

You can review the setting through:

Windows Security → Virus & threat protection → Manage settings

Do not disable real-time protection simply because a website or downloaded program tells you to do so.

A malicious installer may try to persuade users to disable security software before running it.

4. Run a Quick Scan

Even when real-time protection is enabled, you can manually run a malware scan.

For a routine check, start with a Quick scan.

A quick scan examines areas of the system where threats are commonly found.

Consider running a scan if:

• Your PC behaves unusually
• You recently downloaded an unfamiliar file
• You opened a suspicious attachment
• You installed software from an unfamiliar source
• You received an antivirus warning
• You simply want an additional security check

A clean scan is useful, but it does not prove with absolute certainty that a computer is completely free of every possible threat.

5. Use a Full Scan When Necessary

If you have stronger reasons to suspect malware, you can consider a more thorough scan.

Windows Security provides additional scanning options.

A Full scan examines files and running programs across the system and can take significantly longer than a Quick scan.

You do not necessarily need to run a Full scan every day.

It is more appropriate when you have a specific concern or want a more comprehensive malware check.

6. Check Protection History

Protection History is especially useful when reviewing the security of your PC.

Open Windows Security and review Protection history.

Microsoft states that Protection History can show actions taken by Microsoft Defender Antivirus, potentially unwanted apps that were removed, and important security services that are turned off. Protection History retains events for a limited period, so it is worth reviewing warnings rather than ignoring them.

Look for entries such as:

• Threat found
• Threat quarantined
• Threat blocked
• Remediation incomplete
• Potentially unwanted app blocked
• Important security service turned off

If you see a detection, read the details before taking action.

Do not select Allow on device simply because you recognize the filename.

If you are uncertain whether a detected file is safe, leaving it quarantined while you investigate is generally safer than immediately allowing it.

7. Check That Windows Firewall Is Enabled

A firewall helps control network traffic between your PC and other devices or networks.

Open:

Windows Security → Firewall & network protection

Check the network profile currently in use and make sure Windows is not warning that firewall protection is disabled.

You may see profiles such as:

• Domain network
• Private network
• Public network

For most beginners, there is no reason to turn off the firewall during ordinary computer use.

If an application asks for firewall access, make sure you recognize and trust the application before approving the request.

8. Review App & Browser Control

Next, open:

Windows Security → App & browser control

This area includes protections against unsafe applications, files, websites, and downloads.

Microsoft's current Windows Security documentation says App & browser control combines reputation-based protection with exploit mitigation and includes Microsoft Defender SmartScreen-related settings.

Do not casually disable these protections because a download or website asks you to.

A warning may be preventing you from running unsafe software.

9. Check Reputation-Based Protection

Under App & browser control, review Reputation-based protection where available.

These settings can help identify suspicious:

• Applications
• Files
• Downloads
• Websites
• Potentially unwanted applications

Microsoft Defender SmartScreen can evaluate the reputation of apps and files downloaded from the web and can warn about known malicious or phishing websites in Microsoft Edge.

If SmartScreen displays a warning, investigate the website or file before bypassing it.

10. Check Potentially Unwanted App Protection

Not every unwanted application is technically malware.

Some programs may instead:

• Display excessive advertising
• Install additional unwanted software
• Use system resources unexpectedly
• Change browser behavior
• Perform activities you did not expect

Microsoft calls these potentially unwanted applications, or PUAs.

Windows can help identify and block them.

Microsoft recommends downloading apps from trusted sources, keeping antivirus protection updated, and keeping Windows, browsers, and applications current.

11. Check Windows Update

An antivirus program alone cannot secure an outdated operating system.

Open:

Settings → Windows Update

Check for available updates and install important security and system updates.

Updates can fix vulnerabilities that attackers might otherwise exploit.

You should also keep other frequently used software updated, including:

• Web browsers
• Office applications
• PDF readers
• Communication applications
• Security software

Avoid downloading supposed Windows updates from random pop-ups or unfamiliar websites.

Use Windows Update or official software sources.

12. Check Device Security

Open:

Windows Security → Device security

The exact options depend on your hardware.

Microsoft states that Device Security can manage hardware-based and operating-system security features such as Secure Boot, core isolation, security processor features such as TPM, and device encryption settings where supported.

Do not worry if your screen does not look exactly like someone else's PC.

Available security features vary according to hardware and Windows configuration.

However, if Windows reports that an important device-security feature has unexpectedly become disabled, investigate the reason.

13. Check Your Windows Sign-In Security

Physical access to a computer is also a security issue.

Open:

Settings → Accounts → Sign-in options

Review how you sign in to Windows.

Windows Hello can support:

• PIN
• Fingerprint recognition
• Facial recognition

Available biometric options depend on your hardware.

Microsoft describes Windows Hello as a more personal and secure sign-in method and notes that a Windows Hello PIN is associated with the particular device.

Do not leave a personal laptop without any meaningful sign-in protection.

14. Lock Your PC When You Walk Away

Even a malware-free computer is not secure if anyone nearby can access it while you are away.

When leaving your PC unattended, press:

Windows key + L

This locks the computer without closing your applications.

Anyone attempting to use it must then authenticate again.

This simple habit is particularly important when using a computer at:

• Work
• School
• Shared accommodation
• Public spaces
• Offices
• Libraries

15. Review Ransomware Protection

Ransomware can encrypt files or otherwise prevent you from accessing them.

Windows includes ransomware-related protection options.

One important feature is Controlled Folder Access, available through ransomware protection settings.

Microsoft says Controlled Folder Access is designed to protect valuable data from malicious apps and threats such as ransomware by preventing unauthorized or unsafe applications from modifying files in protected folders.

However, security software should never be your only ransomware defense.

16. Make Sure Important Files Are Backed Up

Backups are one of the most important parts of computer security.

A backup can help when files are lost because of:

• Ransomware
• Hardware failure
• Accidental deletion
• File corruption
• Device theft
• Serious software problems

Keep copies of important:

• Documents
• Photos
• Videos
• Work files
• Financial records
• Other irreplaceable data

For particularly important information, avoid keeping the only backup permanently connected to the same PC.

Microsoft also recommends keeping Windows updated and using Windows Security as part of ransomware protection.

17. Review Recently Installed Programs

Sometimes unwanted software appears because a user accidentally installed it along with another application.

Open:

Settings → Apps → Installed apps

Review the list.

Ask yourself:

• Do I recognize these programs?
• Did I intentionally install them?
• Are there applications I no longer use?
• Did something appear around the time problems started?

Do not randomly uninstall unfamiliar Windows components.

If you do not recognize an application, research it first.

18. Check Your Browser Extensions

Browser extensions can access significant amounts of browsing information depending on their permissions.

Open your browser's extension or add-on manager.

Review installed extensions and remove ones that:

• You do not recognize
• You no longer use
• Came from an uncertain source
• Request unnecessary permissions
• Behave suspiciously

Keep the extensions you actually need updated.

A browser filled with unnecessary extensions increases complexity and can increase risk.

19. Review Your Downloads Folder

The Downloads folder often accumulates installers, archives, documents, and other files from the internet.

Periodically review it.

Be particularly cautious with unfamiliar:

• .exe files
• .msi installers
• Scripts
• Compressed archives
• Documents received unexpectedly

Do not open a file simply because its name looks familiar.

If a downloaded file is suspicious, verify its source before running it.

20. Verify Suspicious Files and Links

If you are unsure about an unfamiliar file, URL, or domain, additional security checking can be useful.

Services such as VirusTotal can aggregate results from multiple security vendors and analysis tools.

However, a security scan should be treated as additional evidence rather than an absolute guarantee that something is safe.

Also remember that uploading a file to an online analysis service may have privacy implications.

Do not upload confidential, personal, business-sensitive, or otherwise private files without understanding how the service handles submissions.

21. Watch for Phishing

A secure Windows PC can still be compromised if the user gives an attacker a password.

Be suspicious of messages that:

• Demand urgent action
• Claim your account will immediately be closed
• Ask you to verify a password
• Request a verification code
• Contain unexpected attachments
• Ask for payment through unusual methods
• Send you to an unfamiliar login page

Do not judge a message only by its logo or appearance.

Attackers can copy the design of legitimate companies.

When possible, open the official website or app yourself instead of following an unexpected login link.

For more practical warning signs, read our beginner's guide to identifying phishing links and websites.

22. Check Your Password Habits

PC security also depends on account security.

Avoid reusing the same password across important accounts.

If one website is compromised, reused credentials can put other accounts at risk.

For important accounts:

• Use strong, unique passwords
• Consider a reputable password manager
• Enable two-factor authentication where available
• Keep account recovery information current
• Never share one-time verification codes

A secure computer cannot protect an online account if its credentials are voluntarily given to an attacker.

You can also check whether your email has appeared in a known data breach using Have I Been Pwned.

23. Be Careful With Administrator Permission Requests

Windows may ask for administrator permission when software wants to make important system changes.

Do not automatically click Yes.

Before approving, ask:

• Did I intentionally start this installation?
• Do I recognize the program?
• Did I download it from an official or trusted source?
• Does the request make sense for what I am doing?

Unexpected administrator prompts deserve investigation.

24. Do Not Disable Security Features for Random Software

A particularly suspicious instruction is:

“Disable your antivirus before installing.”

There are legitimate situations where security software can create compatibility issues, but beginners should not disable protection merely because an unknown website or installer says to do so.

The same caution applies when instructions ask you to disable:

• Microsoft Defender
• SmartScreen
• Windows Firewall
• Browser security warnings
• Other Windows protections

Verify the software and instructions independently first.

25. Signs That Deserve Further Investigation

No single symptom proves that your PC has malware.

However, investigate if you notice unexpected:

• Antivirus warnings
• Browser redirects
• Unknown programs
• Extensions you did not install
• Security settings being disabled
• Pop-ups outside normal websites
• Changes to your browser homepage
• Unusual account login alerts
• Files becoming inaccessible
• Ransom demands
• Applications launching by themselves

Performance problems alone are not proof of infection.

Slow computers can also result from storage problems, hardware limitations, background applications, software bugs, or other causes.

26. What Should You Do If You Suspect Malware?

If you believe your Windows PC may be infected:

1. Do not enter sensitive passwords into suspicious windows.
2. Run Microsoft Defender or your active trusted antivirus.
3. Review Protection History.
4. Consider a Full scan when appropriate.
5. Investigate unfamiliar software.
6. Change compromised account passwords from a trusted device when necessary.
7. Verify important account activity.
8. Keep backups safe.
9. Seek qualified technical assistance if the problem is beyond your experience.

Microsoft specifically recommends using antimalware tools such as Windows Security when you are concerned that a PC may be infected.

27. A Simple Windows Security Checklist

For a quick routine review, check the following:

• Windows Security shows no unresolved critical warnings
• Real-time antivirus protection is active
• A recent malware scan shows no unresolved threats
• Protection History has been reviewed
• Windows Firewall is enabled
• Reputation-based protection is active where appropriate
• Windows Update is current
• Important device-security features are not unexpectedly disabled
• Your Windows account has secure sign-in protection
• Important files are backed up
• Browser extensions are familiar and necessary
• Installed applications are recognized
• Suspicious downloads have not been opened
• Important online accounts use unique passwords
• Two-factor authentication is enabled where practical

You do not need to obsessively check every setting every day.

The goal is to establish sensible security habits and investigate meaningful warnings when they appear.

28. Is a Green Windows Security Screen Proof That Your PC Is Completely Safe?

No.

A healthy Windows Security status is a positive sign, but it cannot guarantee that a computer is completely secure.

Security tools have limitations.

A computer can still face risks from:

• New or undetected malware
• Phishing
• Stolen passwords
• Unsafe browser extensions
• Social engineering
• Unpatched third-party software
• Poor backup practices
• Physical access
• User-approved malicious software

Think of Windows Security as one important layer rather than a complete guarantee.

29. How Often Should You Check Your PC Security?

There is no single schedule that fits everyone.

Windows performs many security tasks automatically.

For an everyday user, it is reasonable to pay attention to security warnings as they appear and periodically review:

• Windows Security status
• Windows Update
• Protection History
• Backups
• Installed applications
• Browser extensions
• Important account security

You should also perform additional checks after suspicious activity or an unusual security warning.

30. Final Verdict

Checking whether your Windows PC is secure does not require complicated tools.

Start with Windows Security.

Make sure antivirus and firewall protection are working, review Protection History, keep Windows updated, pay attention to SmartScreen and other security warnings, and check the security features supported by your device.

Then look beyond antivirus.

Review your installed programs and browser extensions, protect your accounts, maintain backups, avoid suspicious downloads, and learn to recognize phishing.

For beginners, the most effective security strategy is not to search for a single tool that promises perfect protection.

Instead, combine built-in Windows protections with safe browsing, updated software, strong account security, backups, and careful decisions.

A short security check performed thoughtfully can reveal problems early and help you maintain a safer Windows PC.

Guide note: This article is based on Microsoft Windows security guidance available in August 2026. Windows Security features and menu options can vary by Windows version, device hardware, configuration, and future software updates. Always check Microsoft's current documentation when a setting on your PC differs from the instructions above.