Updates and antivirus: protecting your computer

How to update Windows, your browser and phone, scan with Microsoft Defender, spot fake virus warnings and what to do if your device is infected.

“Working on updates, don’t turn off your computer” is a message that annoys a lot of people: the work is urgent and the computer spends half an hour restarting. So many people simply switch updates off. In fact, updates and antivirus are the simplest and most reliable way to protect your computer and phone: set them up properly once and they do most of the work for you. In this guide we explain in plain language why updates matter, set up Windows Update so it does not get in the way of your work, and look at updating your browser, programs and phone. Then we cover what antivirus software can and cannot do, how to use Microsoft Defender, which is built into Windows, how to recognise fake “your computer is infected” warnings and what to do if your computer does get infected. At the end there is a practice exercise and a checklist. Menu names follow the English interface of Windows and the programs.

Why updates matter: vulnerabilities and patches in plain language

Every program, whether it is Windows, a browser, Telegram or a banking app, is written by people, and it contains mistakes. Some mistakes are just a nuisance: a button does not work, a window freezes. Others affect security: through them a stranger can get into your computer, read your files or install malicious software. A mistake like this is called a vulnerability.

Think of it like a house. The manufacturer finds out that the model of lock on your front door can be opened with a special wire, and sends every customer a new cylinder. Anyone who has not swapped it is now living with a lock whose weakness burglars know about too. Software works the same way: once a vulnerability is found, the developer releases a small fix called a security patch. From the moment the patch is announced, criminals know about the vulnerability as well, and they target precisely the devices that have not been updated.

That is why an update is not just about new buttons: often its most important part is the security fixes you never see. We cover other reasons a computer slows down in our article on speeding up your computer.

Windows Update: settings and scheduling restarts

In Windows 11 and Windows 10, updates are usually downloaded automatically. Your job is not to switch them off and to make the restart time convenient for you.

Checking for updates

Open Start → Settings → Windows Update (in Windows 10: Settings → Update & Security → Windows Update).
Click Check for updates. Windows finds and downloads the available updates.
If “Restart required” appears, save your work and restart the computer at a convenient moment.
The Update history section shows which updates have already been installed.

Active hours

Windows will not restart the computer on its own during active hours. Set the times manually under Windows Update → Advanced options → Active hours. For example, Dilnoza, an accountant, works from 8:00 to 19:00, so she sets that range and updates are installed in the evening or overnight.

Scheduling the restart

Once an update has been downloaded, the Windows Update page offers Schedule the restart, where you pick a specific day and time. Also turn on Notify me when a restart is required in Advanced options, so the computer warns you before restarting and you have time to save any open documents.

Pausing is a temporary measure

The Pause updates button stops updates for a few weeks, for example during the week of an important presentation. When the pause ends, Windows will install the updates anyway. Do not use it as a permanent solution, and do not install “tweaker” programs that switch updates off.

Updating your browser, programs and phone

Updating Windows alone is not enough: a large share of attacks come through the browser and widely used programs.

Browser

Browsers usually update themselves, but the update only takes effect after the browser is restarted. If you leave your browser open for weeks, an “Update” label or a coloured icon appears in the top-right corner.

Google Chrome: three-dot menu → Help → About Google Chrome.
Microsoft Edge: three-dot menu → Settings → About Microsoft Edge.
Mozilla Firefox: menu → Help → About Firefox.

Simply opening this page checks for updates; finish by clicking Relaunch. While you are at it, remove any extensions you do not use.

Other programs on your computer

Apps installed from the Microsoft Store: Microsoft Store → Library → Get updates.
Office, PDF readers, messengers and other programs usually have Help → Check for updates or a similar option in their settings.
Remove old programs you no longer use through Settings → Apps → Installed apps: a program that has been removed cannot be vulnerable.

Android phones

Menu names vary by manufacturer, but the route is roughly the same:

Settings → System → Software update (or Settings → Software update): system updates.
Settings → Security & privacy → Updates: security updates and Google Play system update (some phones may not have this option).
Google Play → profile picture → Manage apps & device: app updates. You can also turn on automatic updates there.

iPhone

Settings → General → Software Update: system updates. In Automatic Updates on the same page, turn on automatic download and installation. For apps: Settings → App Store → App Updates.

It is best to update your phone while it is connected to Wi-Fi and charging.

Outdated and unsupported systems

Every system has a “lifespan”: after a certain point the developer stops releasing fixes for it. For example, Microsoft ended standard support for Windows 10 in October 2025, and for Windows 7 and 8.1 this happened much earlier. Such a system keeps working, but new vulnerabilities in it are no longer fixed. Older Android phones also stop receiving updates over time.

What to do: check whether your device is still getting updates. If it is not, do not use it for banking apps, government services or important accounts, and where possible move to a newer system or plan to replace the device.

What antivirus does and does not do

Antivirus software detects malware (viruses, trojans, ransomware and so on) on your computer and neutralises it.

What antivirus does:

scans files you download and open;
recognises known malware by its “fingerprint” and behaviour;
moves a suspicious file into quarantine (a separate, safe place);
blocks some dangerous websites and downloads.

What antivirus does not do:

it cannot stop you if you type your password into a fake website yourself: that is phishing;
it cannot prevent you from reading out an SMS code to a scammer who called claiming to be “from the bank”;
it does not close vulnerabilities in a system that has not been updated;
it does not bring back lost or encrypted files: for that you need a backup.

So antivirus is only one layer of protection. The other layers are updates, a strong password with two-step verification, caution and a backup. Passwords and protection against scams are covered in detail in our article on staying safe online.

Windows Security: working with Microsoft Defender

In Windows 10 and 11, the Microsoft Defender antivirus is built into the system, so there is no need to buy or install a separate program. Open it via Start → Windows Security. Green ticks on the home page mean everything is fine; yellow or red icons mean something needs your attention.

Types of scan

Under Virus & threat protection → Scan options there are four types of scan:

Quick scan checks the places where malware most often hides. It is enough for routine checks.
Full scan checks all files and programs. It can take more than an hour, so run it when the computer is free, for example during your lunch break.
Custom scan checks only a folder or USB stick that you choose. It is useful before opening someone else’s USB stick.
Microsoft Defender Offline scan (called “Microsoft Defender Antivirus (offline scan)” in newer versions) restarts the computer and scans it before Windows fully loads. It is designed for malware that hides from a normal scan and resists removal. Save all open files before you start.

Scan results and quarantined files appear in Protection history.

Real-time protection

Real-time protection, under Virus & threat protection settings → Manage settings, should always be on: it checks a file the moment it is opened or downloaded. Some installation instructions for games or “activators” say “turn off your antivirus first”, and that is almost always a warning sign. Defender updates its security intelligence through Windows Update; to check manually, click Protection updates → Check for updates.

Ransomware protection (Controlled folder access)

Ransomware is malware that encrypts your files and demands a ransom to restore them. If you turn on Controlled folder access under Virus & threat protection → Ransomware protection → Manage ransomware protection, only trusted programs can write to Documents, Pictures and other protected folders. Sometimes this setting blocks an ordinary program too; in that case allow it through Allow an app through Controlled folder access.

Do not install two antivirus programs at once

When two antivirus programs run at the same time, they may treat each other’s activity as malicious, slow the computer down noticeably and even weaken your protection. If you install a third-party antivirus, Defender’s real-time protection usually switches off automatically, which is normal. If you later uninstall the third-party antivirus, check in Windows Security that Defender has switched back on. For a home computer, an up-to-date Defender is usually enough.

Fake warnings and fake updates

Scammers exploit people’s trust in updates and antivirus software. The most common situations are:

A “Your computer is infected” window in the browser. When a site opens, you see a red warning, hear a siren and get a “call now” or “clean immediately” button. A genuine Windows Security alert appears as a system notification, not inside the browser. If you see a window like this, do not click anything and do not call anyone: close the tab. If it will not close, open Task Manager with Ctrl + Shift + Esc and end the browser.
A fake update. A website says “Your browser is out of date, download the update” and offers a file such as update.exe. A real browser update only comes through the browser’s own menu (the About page), and a Windows update only through Settings → Windows Update.
“Useful” files on Telegram. For example, Sardor sees an APK or EXE file in a group labelled “new tax calculator”. An installation file from a stranger is one of the most common ways malware spreads.
“Premium for free” and “activators”. Cracked versions of paid programs, game “cheats” and stolen keys often come bundled with malware.

Download programs only from official sources

For a computer: the developer’s official website or the Microsoft Store.
For Android: Google Play; for iPhone: the App Store.
Find a banking or government app through the link on that organisation’s own website.
Check the website address carefully: there are fake domains that differ by a single letter.
On Android, do not give Install unknown apps permission to any app (especially a messenger).

Signs of infection and what to do

Warning signs

your computer or phone is very slow for no reason and the fan is constantly noisy;
the browser’s home page or search engine has changed by itself, and unfamiliar extensions have appeared;
advertising pop-ups keep appearing on the screen;
Windows Security or your antivirus has switched itself off and will not turn back on;
people you know have received messages from your account that you did not send;
files will not open, a strange extension has been added to their names and a ransom note has appeared.

A single sign does not always mean a virus, but it is a good enough reason to check.

What to do

Disconnect from the internet: turn off Wi-Fi or unplug the cable. This stops the malware sending data and spreading.
Do not pay, and do not call unfamiliar numbers offering “help”.
Run a Full scan, then a Microsoft Defender Offline scan. Review any threats found in Protection history.
Change your passwords from another, clean device: your email first, then your bank, social media and messengers. Turn on two-step verification.
Tell your bank if there have been suspicious card transactions or you entered your card details somewhere.
Restore your files from a backup. Paying a ransom for encrypted files does not guarantee you will get them back.
If the problem persists, contact a specialist or consider returning the system to a clean state (Settings → System → Recovery → Reset this PC).

We explain how to set up backups in our articles on backing up your files and cloud storage. The rule is simple: a backup is made before a problem, not after it.

Common mistakes

Switching updates off completely. Avoiding a one-off inconvenience leaves the computer permanently at risk.
Putting off the restart for weeks. The update has been downloaded but does not take effect until the computer restarts.
Turning the computer off during an update. Cutting the power while “Do not turn off your computer” is on screen can damage the system.
Thinking “I have antivirus, so I’m safe”. Phishing and scam calls get round antivirus software.
Trusting warnings in the browser. A website cannot scan your computer.
Downloading a program with an “activator” or from an unknown channel and turning off the antivirus to do it.
Using a banking app on an old phone even after it has stopped receiving updates.

Practice exercise and checklist

The exercise takes about an hour (the time is approximate). Imagine that Aziz wants to tidy up his parents’ home computer and phone. Follow the same steps on your own device.

Open Settings → Windows Update, click Check for updates and install whatever it finds.
In Advanced options → Active hours, set your usual working hours and turn on Notify me when a restart is required.
Open your browser’s About page, check for updates and click Relaunch. Remove the extensions you do not use.
Click Microsoft Store → Library → Get updates.
In Settings → Apps → Installed apps, find programs you have not used for over a year or whose names you do not recognise, and remove the ones you do not need.
Open Windows Security and check that every section is green and Real-time protection is on.
Click Protection updates → Check for updates, then run a Quick scan.
Try turning on Controlled folder access under Ransomware protection; if a program you need is blocked, allow it.
On your phone, check for system and app updates and turn on automatic updates.
Check whether your most important folders are backed up.
Explain to your family what a fake “virus detected” window in the browser looks like and what to do if one appears.

Checklist

Windows, the browser and the phone are up to date, and automatic updates are on.
Active hours are set, and restarts are not being put off.
Only one antivirus is running, and Real-time protection is on.
The latest scan result in Protection history is clean.
Controlled folder access has been tried out.
Programs come only from official sources, and unnecessary ones have been removed.
Important files are backed up.
You know the signs of infection and the first steps (disconnect, scan, change passwords).

Updates and antivirus are not complicated technology; they are a habit. Set aside ten minutes once a month and check your devices against this list. If you would like to explore cybersecurity in more depth, take a look at our association’s free cybersecurity programme, and if you want to learn to use a computer from scratch, our computer literacy programme.

Have a look at our association’s other free training programmes too. When you are ready, submit an application and our specialists will get in touch.