Steps to take if your computer is infected with a virus
If you suspect a virus on your computer system, it’s important to act fast.
Undealt with, computer viruses can cause data loss, compromise personal information, and lead to severe disruptions.
Viruses are especially concerning for businesses, as they run the risk of spreading to other computers and causing financial, reputational, or legal damage. For example, recent malware Zeus infected over 3 million computers, stealing financial information from multiple major global organisations.
But, if you do have a virus, don’t panic. By following the right steps, you can effectively remove the virus and stop it spreading.
Here are some immediate actions to take if you think your computer is infected, along with how to protect your system from future attacks.
Steps to get rid of a computer virus
Follow this step-by-step process to get rid of the virus on a Windows PC or Mac as quickly as possible.
Get rid of a virus on Windows
- Identify the infected machine – Locate the computer that is exhibiting signs of infection and disconnect it from the network immediately to prevent the virus from spreading to other devices.
- Switch to safe mode – Restart your computer and press F8 until the ‘Advanced Boot Options’ menu appears, then select the ‘Advanced Boot Options’ menu. Click ‘Safe Mode with Networking.’ Stay offline.
- Delete temporary files – Use ‘Disk Clean Up’ to delete temporary files that start with your computer which may include the virus. To do this, click the Windows logo and search ‘Temporary Files’ then “Free up disk space by deleting unnecessary files.” Find and select “Temporary Internet Files” in the ‘Files to delete’ Disk Cleanup list and click OK and confirm.
- Run a virus scan – Use up-to-date antivirus software to conduct a comprehensive system scan on the infected machine, ensuring all files and programs are checked.
- Delete the files – Remove any detected viruses and malicious code identified by the antivirus scan.
- Restart your computer – It does not need to be in safe mode.
- Change your passwords – This can protect from reinfection.
Get rid of a virus on Mac
- Shut down the infected program – Close the program or software that is experiencing issues.
- Search for the virus – Open ‘Activity Monitor’ and look for known Mac viruses like ‘MacDefender’, ‘MacProtector’, or ‘MacSecurity’.
- Shut down the virus – If you locate any of these viruses, select them and click ‘Quit Process’ before closing ‘Activity Monitor’.
- Delete files – Then, go to your ‘Applications’ folder and move the infected file to the ‘Trash’.
- Empty trash – Ensure you empty the ‘Trash’ to permanently remove the virus from your system.
- Update your software and applications – Updating to the latest versions will ensure you have the newest security updates.
What is a computer virus?
A computer virus is a type of malicious software, or malware, designed to infiltrate a computer system without the user’s consent. Once inside, it can replicate itself and spread to other files and programs, often causing damage or disruption.
Viruses can:
- Corrupt data
- Consume system resources
- Compromise the security of your personal information
They typically spread through infected email attachments, compromised websites, and file-sharing networks. Unlike other forms of malware, a virus requires user action, such as opening an infected file, to initiate its spread and activation.
How to tell if you have a virus on your computer
If a computer or laptop is experiencing any of these signs, it might have a virus:
- Slow loading or running of programs – This could be a sign that a virus is consuming your system’s resources, making it difficult for legitimate programs to operate efficiently.
- Deleting files – Some viruses are designed to delete or corrupt files.
- Suspicious programs running – Programs you didn’t install could be a sign that malware has infiltrated your system and is executing unwanted tasks.
- On-screen pop-ups – Constant pop-ups can indicate the presence of adware or other malicious software designed to bombard you with unwanted advertisements.
- Antivirus disabled – A common tactic of viruses is to disable your antivirus software, leaving your computer vulnerable to further attacks.
- Computer crashing often – Frequent crashes can be caused by malware disrupting the normal functioning of your operating system.
- Unknown apps running in the background – Background processes that you don’t recognise can be a sign that malicious software is performing unauthorised activities.
How do computer viruses spread?
Many of the most prevalent virus dissemination methods involve human error. They typically spread through:
- Opening an infected email or email attachment
- Utilising flash drives that contain malicious code
- Exploiting vulnerabilities in the operating system
- Declining or delaying a system update and leaving themselves exposed
- Surfing unsafe websites
How to prevent a computer virus
So how do you stop viruses from happening in the first place and keep your systems safe after an incident?
Start by installing and maintaining reputable antivirus software to detect and prevent the latest threats. To ensure the best protection, you can also outsource security services to a provider with relevant certifications and partnerships, such as Sophos and Mimecast. Make sure you consistently keep all software up to date. Activating your computer’s firewall can help block unauthorised access and protect against malicious activities.
Be cautious with emails and attachments, avoiding suspicious senders. And practice safe web browsing by only visiting reputable websites and steering clear of suspicious pop-ups or ads. Additionally, use strong and unique passwords for all your accounts, changing them regularly. Enhance account security by enabling multi-factor authentication (MFA).
Regularly backup important files with Cloud storage and have a data protection and recovery protocol in place in case of an infection. Allow administrative privileges to only key personnel to minimise the risk of unauthorised software installations.
Finally, make sure you have cybersecurity protections in place and educate employees or family members on safe computing habits.
Save costs with preventive vs. reactive measures
When it comes to dealing with computer viruses, the age-old adage “prevention is better than cure” holds true. But how does this translate in terms of cost-effectiveness?
What are the immediate costs of dealing with a virus?
Reactive measures, such as hiring experts to remove viruses and restore systems, can be expensive. The immediate costs can range from hundreds to thousands of pounds, depending on the severity of the infection and the value of the lost data.
What are the long-term costs of a virus?
Beyond the immediate financial burden, reactive measures can also result in long-term costs. These include potential loss of customer trust, damage to brand reputation, and even legal consequences for failing to protect customer data.
What are the costs of preventing a virus?
On the other hand, preventative measures like investing in robust security software and employee training programmes may seem costly upfront but are generally more cost-effective in the long run. Sophos and Mimecast, for instance, offer comprehensive solutions that protect against viruses and offer features like email filtering and data archiving.
Are preventative actions more cost-effective against viruses?
Yes, the ROI for preventative measures is typically higher because they offer ongoing protection, reducing the likelihood of future infections and their associated costs.
While difficult to quantify, the peace of mind that comes with knowing your systems are secure is invaluable. Although not directly translatable to pounds and pence, this psychological benefit contributes to a healthier work environment and can even boost employee productivity.
Get professional help and prevent viruses with peace of mind
Be proactive today and invest in preventative cybersecurity measures to decrease the threat of a security breach. You or your IT team can choose the best antivirus tools for your business, or outsource IT security services with a reputable provider like Arc Systems.
If you require advice on antivirus protection, any other aspect of IT security, or fully managed IT Support, our team of experts will be more than happy to provide you with the information and guidance you need. Get in touch with the team.