What is csrss.exe? Is it a Trojan or Native Windows Process?

Csrss.exe or Client/Server Ru-Time Subsystem/Process is an essential subsystem that has created a lot of confusion among the Windows users whether it is a normal window process or a virus (Trojan). It shows up in task manager in under processes tab and if terminated, you’ll be surprised with the Blue Screen of Death.

This process is responsible for controlling threading and Win32 console window features. Win 32 console is the plain text window in your Window’s API system while threading is where the application splits into several simultaneous tasks. It is also responsible for some parts of 16-bit virtual MS-DOS environment.


Let’s try to find whether it is a Native Window Process or a Trojan.

When csrss.exe is a Native Window Process?

If you go to start the Task Manager and under the processes tab right click on csrss.exe and then choose properties and it shows the location C:\Windows\System32, then it is considered a normal operation or the Native Client Server Runtime Process.

You can manually locate csrss.exe by going to C:\Windows\System32, however; the program itself is not visible, needless to say that it is a trustworthy file from Microsoft.

Is csrss.exe Harmful for My Computer?

Overall, it is considered safe and it is very rare that it can infect your system. It is always recommended to keep a regular scan check of your system’s safety.

Why You Must Not Stop csrss.exe?

As mentioned-earlier, this program should not be stopped.

It is a crucial process for your PC to work properly. When terminated, it usually results in Blue Screen of Death and in some cases very slow speed, halting your system and may even manipulate system resources.

Unless you have a solid proof that it is a malware and you are aware of the proper method to remove malware, you should continue. Otherwise, you may end up messing up your windows installation.

I’m Not Able to Find Any Information Against my csrss.exe – What to do?

It’s unlikely for you to go to task manager>processes>csrss.exe>properties and find nothing. However, if you are unable to find the file path or there is no such option as Properties, simply click on “show processes from all users” and then right click on the csrss and you’ll be able to see the file path. You may come across a few different csrss process which might include the following:

  • Amd64_microsoft-windows-csrss in c:\windows\winsxs\backup
  • exe.mui in c:\windows\system32\en_US.
  • exe.mui in c:\windows\winsxs\amd64_microsoft-windows-csrss…
  • exe.mui in c:\windows\sysWOW64\en-us
  • exe.mui in c:\windows\winsxs\x86_microsoft-windows-csrss.re…
  • exe in c:\windows\system32.
  • exe in c:\windows\winsxs\amd64_microsoft-windows-csrss…

All these are legit and there is nothing to worry about if you see one or all of these processes running in the task manager.

When CSRSS.EXE is a Trojan?

While there is a very minimal risk of this process being a Trojan but sometimes there can be a symptom of a virus or infection.

Here are a few instances where csrss.exe might be a Trojan.

  • If the csrss is located in a subfolder of the user’s profile folder, then there is a 68% threat that it is a malware.
  • If it is located in a C:\Windows folder, there is a 74% security threat.
  • If it is in a subfolder inside c:\program Files, there is a 57% threat.
  • It may also be located in Windows folder for temporary files. If so, there is a 70% threat of it being a Trojan.
  • If it is in a subfolder of c:\, then there is a 59% security rating of it being dangerous.
  • In other instances, it might be registered as a Trojan in which it might be found as Trojan.W32.Rontokbro, Trojan.W32.Sober, Trojan.W32.Beagle and Trojan.W32.Virkel.

Final Words

You don’t need to panic if you see this process in your Task Manager.

Unless it is slowing down your PC’s performance, there is a threat of it being a Trojan in which you should consider running an anti-virus program. These are commonly used in keyloggers.