Microsoft Corporation•Safe
csrss.exeWhat is csrss.exe?
csrss.exe is a legitimate Windows system process called the Client Server Runtime Subsystem. It is part of Windows itself and is normally safe to see ...
ntoskrnl.exeSafeWhat is ntoskrnl.exe?
Publisher: Microsoft CorporationTypical location:
C:\Windows\System32\ntoskrnl.exentoskrnl.exe is a legitimate Windows system file from Microsoft. It is the Windows NT kernel, which is a core part of the operating system that helps your computer start, run programs, and manage hardware.
What it does
ntoskrnl.exe is responsible for essential low-level Windows tasks such as memory management, process scheduling, hardware communication, and security checks. You do not normally open or manage this file directly because Windows depends on it to function.
Is it safe?
Yes, the real ntoskrnl.exe is safe and should be left alone. It is a core operating system file, not a third-party app. However, malware can sometimes disguise itself using this exact name, so check the file location and digital signature if you are unsure. The genuine file is usually in C:\Windows\System32\ntoskrnl.exe and should be signed by Microsoft Corporation.
Why it causes high CPU or disk usage
- 1Heavy app or background workload is making the kernel work harder
- 2Driver problems, especially graphics, storage, or network drivers
- 3Windows updates or system maintenance running in the background
- 4Memory pressure or paging caused by too many open apps
- 5Malware or a fake file pretending to be ntoskrnl.exe
How to check if it's legitimate
- In Task Manager, right-click the process and choose Open file location.
- Confirm the file is in
C:\Windows\System32. - Right-click the file, open Properties, and check the Digital Signatures tab for Microsoft Corporation.
- If the file is in a strange folder, has no Microsoft signature, or looks duplicated, treat it as suspicious.
- Run a full malware scan if the location or signature does not match the legitimate Windows file.
How to remove it
You should not try to delete the real ntoskrnl.exe. Removing it can make Windows fail to boot. If CPU or disk usage is high, focus on the cause instead: restart your PC, install Windows updates, update device drivers, close heavy apps, and scan for malware. If the file is not in C:\Windows\System32 or is not signed by Microsoft, it may be a fake and should be checked with a malware scan.
Recommended fixes
Restart your device
A restart clears temporary state that often causes transient errors.
- Save your work and close open apps.
- Restart the device from the power menu.
- Reproduce the issue to check whether it persists.
Install Windows updates
- Open Settings > Windows Update.
- Click Check for updates and install everything available.
- Restart if prompted.
Update your drivers (Windows)
- Open Device Manager.
- Right-click the affected device and choose Update driver.
- Select Search automatically for drivers.
Run System File Checker and DISM
- Open Command Prompt as administrator.
- Run
sfc /scannowand let it complete. - Then run
DISM /Online /Cleanup-Image /RestoreHealth. - Restart your PC.
Scan for malware (Windows)
- Open Windows Security > Virus & threat protection.
- Run a Full scan.
- Quarantine or remove anything detected, then restart.
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