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Resolving Csrss.exe 100% CPU Usage Problems
Purpose of Csrss.exe
The csrss.exe file belongs to the Microsoft Client Server Runtime Server subsystem that is used by Windows to manage most of the graphical instruction sets. This feature makes csrss.exe a critical component of your Windows computer and terminating this process may lead to a stop error, commonly known as Blue Screen of Death or BSOD error.
By default, the csrss.exe file is located in C:\Windows\System32. The process was first introduced with Windows NT. Therefore, you will not find the csrss.exe file in Windows 98 or any other Windows operating systems that were released before Windows NT.
The csrss.exe process is the controller of the Win32 console and threading features. In the Windows API (Application Programming Interface) system, Win32 is a plain text window that can be used by programs without requiring the display of images. Threading happens when an application splits into multiple tasks that are run simultaneously. Threads that csrss.exe supports are not the same as the processes.
Usually, a process is split into multiple threads and all threads share the resources within the same process and they run at CPU level. Csrsss.exe helps in creating and deleting threads as and when required. Certain portions of the 16-bit virtual MS-DOS environment are also controlled by the csrss.exe process.
Problems with Csrss.exe
One common problem that users face is that when you right-click something in the Windows Explorer window or the Desktop, the csrss.exe process shows 100% CPU usage.
Note: You can check the CPU usage of a process on the
Processes tab of the Windows
Task Manager. In Windows XP, you can display Task Manager by pressing the
Ctrl +
Alt +
Delete. You may also right-click on the taskbar and then select Task Manager.
Cause of the Error
This 100% CPU usage problem by the Csrss.exe process occurs if the user profile with which you are logged on to your computer is corrupt.
Resolution Method
To resolve this issue, you need to delete your existing profile. Before deleting, remember to make a backup of your files in the My Documents folder because once a profile is deleted, you will not be able to recover these items. If you use the default locations to save your content, then the following are a few more things that you may choose to backup:
- Emails
- Address Book
- Favorites
- Any document templates that you would have created
- Any files stored on your Desktop
Next, log off and then log on to the system as an administrator. Now, on the Desktop or in Windows Explorer right-click
My Computer and then, select
Properties. Display the
Advanced tab page, and then, in the
User Profiles section, click
Settings. Select the corrupt profile from the list and then click the
Delete button.
Csrss.exe is also registered as a Trojan that enables hackers and attackers to gain access to your PC from a remote location and then steal your personal and confidential data, such as passwords, Internet Banking details, and other personal files and folders.
To ensure that the csrss.exe file running on your computer is legitimate and not a virus, you are recommended to use an antivirus tool, such as
Antivirus Plus and an Antispyware tool, such as
StopZilla to search for any malicious data on your PC and remove them.
Virus and spyware are known to add malicious registry entries, as well as new registry entries that may be used to prevent various applications on your computer from functioning properly. These malicious programs may also add entries that enable them to load at system Startup.
To combat these harmful entries, we recommend that you use a registry tool, such as
RegGenie to perform a thorough registry scan and delete all unwanted and malicious information residing in your system registry.
