How to Remove Malware from Windows and Mac PCs?

One thing to be aware of when using a PC at work is the risk of malware infection, which can cause malicious damage.

It is important to prevent malware infection in the first place, but even if infected, it can often be removed, so it is important to understand how to remove it.

This article explains the steps to take to remove malware if a Windows or Mac PC becomes infected.

What to Do First If Infected with Malware
1. Disconnect from the Network
2. Contact Security Personnel
How to Remove Malware from Your PC
1. How to Remove Using Dedicated Security Software
2. How to Remove Malware on a Windows PC Without Dedicated Security Software
3. How to Remove Malware on a Mac PC Without Dedicated Security Software
4. What to Do If You Still Can’t Remove It
What to Do After Removing Malware
1. Reconfirm the Impact of the Infection
2. Identify the Source of the Infection
3. Formulate and Implement Measures to Prevent Recurrence
Summary

1. What to Do First If You Think You Are Infected with Malware

If a PC is infected with malware, there may be signs.

In general, if the following phenomena occur, you should suspect a malware infection and take initial action.

Notifications from security software appear on the screen
You find programs that you don’t remember installing
Your PC is extremely slow

If there is a possibility of malware infection, there are things you should do before attempting to remove it. These are “Disconnecting from the network” and “Contacting security personnel“.

1-1. Disconnect from the Network

If there is a possibility of malware infection, first disconnect the PC from the network and put it in an offline state.

By being offline, you can prevent the spread of infection to other PCs on the network, as well as the outflow of information through remote control.

In particular, if you are using a PC in a company, it is connected to a large number of PCs via the network, so you need to disconnect it immediately.

1-2. Contact Security Personnel

If a PC used in the company is infected with malware, immediately contact the security personnel without dealing with it yourself and check how to respond.

If there is damage that cannot be dealt with internally, you can also ask a company that specializes in removing malware to do so. Please contact globalsupport@jiran.com for assistance.

2. How to Remove Malware from Your PC

Once you have disconnected your PC from the network, the next step is to start removing the malware.

This article explains “How to remove using dedicated security software” and “How to remove without dedicated security software”.

However, we recommend using dedicated security software as it is often functionally superior.

2-1. How to Remove Using Dedicated Security Software

For malware removal, the most effective method is to install security software.

Commercially available security software has many features that are useful for removing malware and can handle almost all situations.

To remove malware using security software, follow these three steps:

① Run a Full PC Scan

First, perform a full PC scan to narrow down the target malware and infected files.

Generally, security software automatically scans regularly, but by performing a complete scan manually, you can find it more reliably.

② Remove Malware and Isolate Infected Files

If a malware infection is discovered, use the security software’s scanning function to remove it as is.

If a file that has already been infected with malware is found, you will have to choose either “delete” or “isolate”.

“Delete” means trying to remove the malware part from the file infected with malware and restore it to its original normal file, and “isolate” means moving the file infected with malware to a folder that cannot be executed.

However, in order to completely eliminate the effects of malware, it is desirable to isolate the infected file and then delete the entire file.

③ Restart PC and Rescan

Once the discovered malware has been removed, restart your PC and rescan.

If you can confirm that there are no other threats, the malware removal is complete.

If you do not know how to use the security software, use a PC that is not infected with malware to check the security software vendor’s support page.

For additional assistance, please contact globalsupport@jiran.com.

2-2. How to Remove Malware on a Windows PC Without Dedicated Security Software

If you are infected on a PC that does not have security software installed, you will need to try to remove it using the OS standard function.

Windows has Windows Defender as a standard function, which is a tool for detecting and removing malware from Windows PCs.

The steps to remove malware using Windows Defender are as follows.

① Open Windows Security settings and select “Malware & threat protection” > “Scan” options.

② Select “Windows Defender Offline Scan” > “Scan Now”. (The PC will automatically restart when the scan is complete)

③ After restarting, open Windows Security settings again and select “Malware & threat protection” > “Protection History” to confirm that the malware has been removed.

For additional assistance, please contact globalsupport@jiran.com.

2-3. How to Remove Malware on a Mac PC Without Dedicated Security Software

Macs are said to be safer than Windows, but with the increase in iPhone users, the number of Mac users is increasing worldwide, and malware specifically for Macs has also been discovered.

MacOS has a feature called Xprotect that automatically scans downloaded files and checks for malware, but if you find an application that may be malware, follow the steps below to remove it.

① Launch “Activity Monitor” and check if any suspicious processes are running.

② Stop the suspicious application that is the source of the suspicious process.

③ Open the “Applications folder” and check the relevant application.

④ Use another PC to search the Internet for suspicious processes and suspicious applications to identify whether they are malware.

⑤ If it is malware, delete the corresponding application.

For additional assistance, please contact globalsupport@jiran.com.

2-4. What to Do If You Still Can’t Remove It?

If it is difficult to remove with security software, or if the malware infection is progressing and cannot be removed, it may be necessary to initialize the OS.

However, if you initialize it, the PC will return to the state it was in when it was shipped, and all previous data will be lost, so please consider this as a last resort. Please contact globalsupport@jiran.com for assistance.

3. What to Do After Removing Malware

Even if you have successfully removed malware from an infected PC, there are things you should do to minimize damage and prevent recurrence.

Here are three points to do after removing malware.

3-1. Reconfirm the Impact of the Infection

First, check if there are any other PCs infected with malware, and if you find any, remove them using the same procedure.

Also, in order to prevent the PC from being attacked in the future, and considering the possibility that the password has been leaked, it is desirable to change the password related to the infected PC.

3-2. Identify the Source of the Infection

It is also important to identify the source of the infection in order to prevent malware infections from occurring again.

Check the operation history of the infected PC, or the firewall and proxy server logs of the security software at the infrastructure level, and investigate suspicious traces.

For assistance, please contact globalsupport@jiran.com.

3-3. Formulate and Implement Measures to Prevent Recurrence

Formulate and implement measures to prevent recurrence based on this incident.

There are five general measures to prevent recurrence:

Update the OS and software on your PC to the latest version
Install security software on all PCs
Investigate the infection route and close the security hole based on the results
Back up important files regularly
Improve user awareness of security

For assistance, please contact globalsupport@jiran.com.

Summary

It is important to prevent malware infection in the first place, but even if it slips through the cracks and becomes infected, it is necessary to calmly assess the situation and take appropriate measures.

By making calm judgments and taking action, you may be able to remove malware and shut out cyber attacks.

For assistance, please contact globalsupport@jiran.com.