How to fix error error-sem-not-found in Windows 11

Solution Steps

1. 1 Restart your computer. This clears all semaphores and resets the system to a clean state. Often, this error is temporary and a reboot fixes it.
2. 2 If the error occurs with a specific program, close all instances of that program. Press Ctrl+Shift+Esc to open Task Manager, find the program in the 'Processes' tab, right-click it, and select 'End task'. Repeat for all instances. Then relaunch the program.
3. 3 If the program is still running in the background, use Command Prompt to force kill it. Open Command Prompt as administrator (Win+X → Terminal (Admin)), type 'taskkill /f /im program.exe' (replace 'program.exe' with the actual executable name) and press Enter. This forcefully terminates the process.
4. 4 Check for a corrupted program installation. Uninstall the program via Settings → Apps → Installed apps, then reinstall it. This ensures all files are fresh and semaphores are properly created.
5. 5 If the error occurs system-wide, run the System File Checker. Open Command Prompt as administrator and type 'sfc /scannow' and press Enter. This repairs corrupted system files that might affect semaphore creation.