You never interact with it directly as a user.
What Is Client Server Runtime Process?
This is the display name that Windows uses for csrss.exe, which stands for client server runtime subsystem.

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The Client Server Runtime Process has been around since the early days of Windows.
Before 1996, it was responsible for the graphical subsystem.
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Is It Safe to Disable Csrss.exe?

That means you might’t kill, disable, delete, orquarantine csrss.exewithout experiencing severe consequences.
If youkill a legitimate csrss.exeprocess, your system may become unstable.
In most cases, your rig will shut down.

What Causes Csrss.Exe to Use Excessive GPU or CPU?
Under normal circumstances, csrss.exe should only use a small amount of system resources.
If you’re using Windows 7, you should disable Aero.

In most cases, the cause behind csrss.exe using excessive resources is that you’re dealing with a fake.
Could Csrss.exe Be a Virus?
This is because legitimate copies of the csrss.exe file are only found in two different folders.

Scroll down to theWindows processessection.
Tap-and-hold or right-clickClient Server Runtime Process,and selectOpen file location.
Verify that thecsrss.exeprocess is located in your%SystemRoot%\System32or%SystemRoot%\SysWOW64folder.
Pay close attention to the file name.
If one letter is different from csrss.exe, it’s probably malware.
Repeat these steps for each instance of Client Server Runtime Process that you see in your Task Manager.
In those cases, you’ll want to use abootable antivirus tool on a flash drive or CD.
FAQ
The csrss.exe Trojan is a malware file masquerading as a csrss.exe file.
This malicious system can steal your personal data and lead to data loss and identity theft.
If you suspect malware, use a reputable antivirus system to perform a full system scan.