5 Free Tools to Find Spyware and Adware on Your PC

Malware can easily sneak onto your computer and hide there undetected. However, with the right tools, you can scan your system and remove spyware, adware, and other malicious programs that may be lurking on your system.

1. Process Explorer

The Process Explorer tool is part of Microsoft's Sysinternals suite of programs, providing extended functionality and replacing pre-installed tools such as Task Manager . In the case of Process Explorer, the program provides information about the handles and DLLs that processes running on the system have opened or loaded.

The program makes it easy to identify malicious DLL files running on your system and determine which programs are using them. It is also useful for tracking DLL version issues, resolving leaks, and providing information about how Windows and applications are working.

It may seem intimidating at first, but the program's interface is incredibly user-friendly, and spending some time with it will help you understand the purpose of the many fields and buttons. Additionally, Microsoft's Process Explorer documentation contains important information about how the tool works and how to use it more effectively.

For regular Windows users, Process Explorer is simply an upgraded Task Manager. Not only can you see what processes are running on your system and how much system resources they’re consuming, but you can also run a VirusTotal scan directly from within the tool. This feature provides an early check and an overview of potential malware on your system. It allows you to compare a process’s hash with known good and bad hashes, which can help you figure out if a process is malicious or not.

You can also use Process Explorer to monitor the network activity being run by a specific process. Right-click the process you want to check, select Properties , and then navigate to the TCP/IP tab . You'll be able to see all the active network connections that process is using—a handy way to check if a program on your PC is connecting to a malicious server. One minor drawback to this feature is that Process Explorer doesn't show a history of network connections; however, it's useful for identifying malicious processes that are currently running.

Last but not least, Process Explorer also displays the Command Prompt commands a particular program requires to launch simply by hovering over the process for a few seconds. Examining the command can reveal special keys, flags, or instructions that a malicious program might use to access system resources.

2. Autoruns

Also part of the Sysinternals suite, Autoruns replaces the Startup apps tab in Task Manager, showing all the applications that start up as soon as Windows fully loads. It also shows all other processes, including DLL files, services, scheduled tasks, and even registry entries — all categorized under clearly defined tabs.

Autoruns makes it easy to detect any malicious executables, DLLs, and tasks that might start with your Windows system. Malware often adds scheduled tasks to Windows, allowing it to start with your system and maintain its continuity automatically. With Autoruns, you can quickly check for suspicious processes, run a VirusTotal scan if necessary, and terminate them.

In addition to hunting down spyware and other malicious programs, Autoruns is also great for optimizing your PC. Instead of having to switch back and forth between multiple settings windows scattered throughout Windows, you can disable all the unwanted programs and processes that start up with Windows in one go. This feature is also useful when troubleshooting Windows to check for any programs that may be causing problems or system instability during startup.

3. VirusTotal

VirusTotal is the easiest and perhaps most basic of all the tools you should use to check if a suspicious program is malicious in any way. In addition to checking individual files for malicious content, the site also allows you to check URLs , hashes, IP addresses , and domains against a database.

This allows you to quickly check whether a file or URL that a process on your PC is communicating with is malicious or not. It is also one of the easiest ways to check whether a downloaded file is safe before using it.

This tool checks your files with over 60 antivirus engines from different vendors. Since antivirus programs vary and can't always identify a malicious file, VirusTotal is a great way to check a file with as many antivirus engines as possible in just a few clicks.

4. Malwarebytes

Malwarebytes is one of the best antivirus and anti-malware programs you can install for free. It often finds files that other antivirus programs miss, including Windows Security, Microsoft's built-in antivirus solution for Windows.

Malwarebytes is particularly good at detecting adware. It can also quarantine and remove adware built into Microsoft tools like Edge , which Windows Security will ignore. It also has a built-in toolkit that lets you tweak Windows privacy settings and control startup apps. If you opt for a Malwarebytes subscription, you also get a built-in VPN and additional protection options, as well as the option to enable real-time system scanning to detect incoming threats.

5. Spybot – Search & Destroy

Spybot is definitely outdated at this point. However, despite its outdated user interface, it is still a really useful tool for finding and removing adware and spyware from your computer, as it specifically targets them. Spybot comes with an additional antivirus component, but it is not included in the free version.

Even without an antivirus tool, Spybot is a useful anti-spyware application to use as a supplement to an existing antivirus program. The setup process is also intuitive and allows you to choose between setting up the tool for automatic protection or configuring the settings manually.