Recently, some users reported getting the error message “sihost.exe – System Warning Unknown Fatal Error” (also known as unknown unrecoverable sihost.exe error) when accessing Windows 10, especially after starting Windows 10. Windows 10 April 2018 update 1803. This error also appeared while starting a program or game, or even after going through a Windows recovery cycle. Sometimes other error messages like B. Ctfmon.exe Unknown Fatal Error and Explorer.exe Unknown Fatal Error also appeared. These error messages may indicate that the operating system contains corrupt or damaged system files, or that there are conflicts between third-party software and the updated Windows system. To solve this problem, you can try the following solutions.

The sihost.exe file is an important software component of Microsoft Windows. It is an integral part of the infrastructure host shell’s operation and is not to be removed. Over the past few years, many Windows 10 users have encountered an unknown fatal sihost.exe error when using Cortana or after installing Windows updates.

After analyzing detailed user reports and articles, we can conclude that the sihost.exe system warning error might have been caused by recent software changes. In addition, corrupted system files and hard drive errors may cause unknown sihost.exe hard drive error.

Perform a clean restart.

Sometimes an unknown sihost.exe hardware error may be caused by a specific program. To determine if a program is causing the problem, we recommend performing a clean reboot. Here’s how:

Step 1: Press the Win + R keys to open the Run dialog box. Then type msconfig and press Enter to open the system configuration window.

Step 2. Click the Services tab. Then check the Hide all Microsoft services checkbox.

Step 3. Now click the “Disable All” button, and then click “Apply” to save this change.

Step 4. Click the Start tab and then click Open Task Manager.

Step 5. Click the “Start” tab and disable all applications one by one until you are sure which one is causing the sihost.exe error. You can then uninstall the program.

Perform an SFC scan.

What is sfc-scannow

Sometimes corrupted system files are also a major cause of errors and bugs. Run the sfc / scannow command in the command line window to scan your local drives for corrupt or damaged system files. The command not only scans disks for errors, but also fixes problems with corrupted system files.

Follow these steps to run the SFC scan from the command line.

Once the command is executed, any corrupted system files detected during the scanning process are displayed. If no corrupt system files are found during the scan, the message “Windows resource protection has not detected any integrity violations” is displayed.

Update the video driver

If the installed device drivers are outdated, corrupt or incompatible with the current version of Windows, this will result in an unknown hardware error. In particular, if you get this error while playing a game, it’s mostly due to an outdated display driver.

Open the Device Manager with devmgmt.msc.

A list of all installed device drivers will appear.

Here you are looking for a pilot with a yellow exclamation mark

Try updating or reinstalling the driver. In particular, reinstall the display driver to remove the currently installed driver from the Device Manager. Visit your device manufacturer’s website (for laptop users – Dell, HP, Lenovo, Asus, etc. And if you are using a desktop computer, visit the motherboard manufacturer’s website) and download and install the latest display driver. Reboot Windows and make sure there are no more unknown fatal errors.