What this means is that the Shell Infrastructure Host (Sihost.exe) process, which is used for handling graphical elements has crashed.
Shell Infrastructure Host process plays an important role in generating Windows user interface elements for users to interact with. It is thus an important process.
Shell Infrastructure Host has stopped working
The following fixes should help us in overcoming the Shell Infrastructure Host has stopped working on Windows 11/10-
1] Reinstall Microsoft Redistributable Packages
The Microsoft Redistributable Package is a package of Microsoft C++ components that are required to run some Windows-specific applications made with Visual C++. You can see many of these files installed on your PC. You may need to reinstall this package as it has been known to help people. From the WinX Menu, open the Run box, type in appwiz.cpl and then hit Enter to open up Programs and Features section of the Control Panel. From the list of programs generated, you can select the listings called Microsoft Visual C++ xxxx Redistributable (x64) and Microsoft Visual C++ xxxx Redistributable (x86).
Right-click on them and click on Uninstall to uninstall it from your computer, and then reboot your computer. Now, get and install the latest releases of the Microsoft Redistributable Package packages from Microsoft Download Center.
2] Run System File Checker
It is quite possible that the system file may have become corrupted. As such, you may want to Run System File Checker and see if that resolves your issue.
3] Use a fresh Guest Account
Ask your admin to delete the old Guest Account and create a new one and see if that resolves your issue.
4] Troubleshoot in Clean Boot State
You can troubleshoot in Clean Boot State to see which third-party Services or Processes may be causing the issue. A Clean Boot starts a system with minimal drivers and startup programs. When you start the computer in clean boot, the computer starts by using a pre-selected minimal set of drivers and startup programs, and because the computer starts with a minimal set of drivers, some programs may not work as you expected. I hope something here helps you.