Key takeaways
- Pop-ups, a changed homepage and unknown programs are the common signs.
- Disconnect from the internet, then run a full Windows Security scan.
- Change your passwords from a clean device, and back up your files.
Common signs of malware
- Pop-ups and ads appearing even when no browser is open.
- A changed homepage or search engine.
- Programs you did not install.
- The laptop is slow and the fan runs hard when you are doing nothing.
- Your antivirus is switched off and will not turn on.
- Files that will not open, or a message demanding payment.
Disconnect first
Turn off Wi-Fi or unplug the network cable. This stops malware from sending your data or spreading while you work on it.
Run a full scan
Open Windows Security, choose Virus and threat protection and run a full scan. You can also run the Microsoft Defender Offline scan, which restarts the laptop and scans before Windows loads.
Remove unknown programs and extensions
Open the list of installed apps and remove anything you do not recognise. Check browser extensions and delete the ones you did not add. Reset the browser settings if the homepage keeps changing.
Secure your accounts
From a clean device such as your phone, change the passwords for your email, banking and social accounts. Turn on two-step verification where you can.
If a message demands payment
Do not pay. Switch the laptop off and bring it to a technician. If you have a backup, your files may be safe.
Prevent it
- Keep Windows and your browser updated.
- Avoid cracked software and unknown flash drives.
- Do not click links in unexpected messages.
- Back up your files regularly.
Frequently asked questions
How do I know if my laptop has a virus?
Look for pop-ups, changed browser settings, unknown programs, a very slow laptop and a switched-off antivirus. A full scan confirms it.
Is Windows Security enough?
For most users, yes, when it is kept up to date and combined with careful habits. A technician can set it up properly.
Should I reinstall Windows after a virus?
Only as a last step. Try the scans and clean-up first, and back up your files before any reinstall.
We repair laptops and build websites and business systems. Have a question this guide did not answer? Message us.
This guide is general advice. Every device and business is different, so if you are unsure, ask a technician before you act.
