The Client/Server Runtime Subsystem process (csrss.exe) is a Windows process that is absolutely essential for system operation. The csrss.exe process is, in the most recent versions of the Windows Operating System, responsible for the handling of the Win32 console and GUI shutdown. In the case of some Windows users, the csrss.exe process has been known to abruptly start taking up almost all available CPU and memory completely out of the blue, causing system to either fail and crash entirely or become so sluggish that it becomes inoperable.
This issue can be caused by one of two things – a corrupt user profile or a virus or malware that has the same name (csrss.exe) as the legitimate Windows system process. Regardless of which of these two is the cause of the problem in your case, rest assured as there definitely is something you can do on your end to try and fix the issue.
However, before you can do something to try and fix the issue, you need to first determine exactly what is causing it. If you simply press Ctrl + Alt + Delete, open your Task Manager and navigate to the Processes tab, you will be able to see just how many csrss.exe processes are running on your computer at the same time. If there are two (or more) csrss.exe processes running on your computer and one of them has absolutely nothing or something fishy in the User name and or Description fields, you can be almost entirely certain that the cause of this problem in your case is a virus or malware.
If the culprit is a virus or malware:
- Click here and, depending on the version of Windows that you are using, download the 32-bit or 64-bit version of the Farbar Recovery Scan Tool. Move the downloaded file to your Desktop. Execute the downloaded file.
- Click on Yes in the disclaimer. Click on Scan.
- Wait for the utility to scan your computer for viruses, malware and other security threats. Once the utility has worked its magic, peruse its results and the log file that it created on your Desktop (or wherever the utility’s executable file that you downloaded was when you ran it) to find out whether or not a virus, malware, Trojan or other security breaches actually is to blame for a csrss.exe process on your computer that takes up almost all of its CPU and memory.
- If you do find a virus, malware or other security threat to be responsible for this problem, you should then download an antivirus and anti-malware program such as Malwarebytes and use it to get rid of all the malicious and potentially harmful elements on your computer.
If the culprit is a corrupt user profile:
If the culprit wasn’t a virus, malware or other malicious file or if the method described above didn’t work, it is possible that the problem was actually being caused by a corrupted user profile. If that is the case, simply creating a new user profile and deleting your old one should fix the issue and get your computer’s csrss.exe process back to using only a minimal amount of CPU and memory. Before you delete your user profile, be sure to back up all the data in your Documents folder and Desktop. Make sure to back up important files before proceeding with this solution.
- Open the Start Menu. Click on your user account’s display picture.
- Click on Manage another account. Click on Create a new account. Name the new account and be sure to select Administrator, and then click on Create account. Double-click on your primary account. Click on Delete the account. Click on Delete files and then on Delete account to confirm the action.
- Log into your new account, and once you do, the corrupt user profile will be replaced with a fresh, new and complete one.
- If you do not want to delete the old account because it has your important files, then before proceed within deletion make sure you back non-executables (My Documents, My Pictures, WORD Files etc) to an external disk drive and after the creation of new profile/deletion of old profile, copy them over to the new profile.