api-ms-win-crt-runtime-l1-1-0.dll Missing
What is this error?
The Universal C Runtime (UCRT) DLL is missing. This is a core Windows component required by virtually all modern applications and games.
Common causes
- Windows Update failed to install KB2999226
- corrupted Windows Update components
- Visual C++ 2015+ Redistributable installation failed
- Windows system file corruption
How to fix it
- Install Windows Update KB2999226
- install Visual C++ 2015-2022 Redistributable
- run Windows Update troubleshooter
Too many steps? Crashless can diagnose this automatically — checks your drivers, temps, VRAM, and 400+ known error patterns.
Get free AI diagnosis Detailed analysis
"api-ms-win-crt-runtime-l1-1-0.dll is missing" means the Universal C Runtime isn't installed on your system. This is a core Windows component that should be present, but sometimes Windows Update fails to install it properly.
This error can block virtually any modern game or application from launching.
How to fix it:
- Run Windows Update — install all pending updates, especially KB2999226 (Universal C Runtime) and KB2919355
- Install the latest Visual C++ Redistributable 2015-2022 from Microsoft (both x86 and x64) — this includes the UCRT
- If Windows Update is stuck, run the Windows Update Troubleshooter: Settings > System > Troubleshoot > Other troubleshooters > Windows Update
- Manually download and install KB2999226 from the Microsoft Update Catalog if automatic updates aren't working
- Run 'sfc /scannow' followed by 'DISM /Online /Cleanup-Image /RestoreHealth' in an admin Command Prompt
- If nothing works, try resetting Windows Update components: stop the wuauserv service, rename the SoftwareDistribution folder, restart the service
When to seek help
If this error keeps happening after trying the fixes above, it may point to a deeper hardware or system issue. Consider professional help if:
- The crash occurs across multiple games or applications
- You see the same error after a clean Windows install
- Your PC is less than a year old (could be a warranty issue)
- You smell burning or hear unusual sounds from your PC
Or let Crashless do the deep analysis for you -- our AI checks drivers, temps, event logs, and 400+ known patterns automatically.
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