Why is this not included with Visual C++ Redistributable?

The UCRT is an OS component, not an application component. Visual C++ depends on it but does not bundle it.

Does Windows 10 need this fix?

Windows 10 includes UCRT by default, but if system files are corrupted, running sfc /scannow and Windows Update should fix it.

api-ms-win-crt-runtime-l1-1-0.dll Missing Error

Errordll errors

Overview

The error api-ms-win-crt-runtime-l1-1-0.dll is missing indicates the Universal C Runtime (UCRT) is not installed, usually fixed by installing Windows updates.

Key Details

Part of the Universal C Runtime (UCRT) included in Windows 10+
On Windows 7/8, requires KB2999226 update to be installed
Common after clean installs of older Windows without running updates
Required by modern Visual C++ applications and Python
The DLL is an API set forwarder, not a traditional DLL file

Common Causes

Windows 7/8.1 missing KB2999226 (Universal CRT) update
Windows Update service disabled preventing automatic installation
Corrupted Windows Update components blocking KB2999226
Clean Windows installation without subsequent updates
Visual C++ Redistributable installed before UCRT prerequisite

Steps

1On Windows 10/11: run Windows Update to ensure all updates are installed
2On Windows 7/8: download and install KB2999226 from Microsoft Update Catalog
3If KB2999226 fails, install KB2919355 first (prerequisite on Windows 8.1)
4Reinstall Visual C++ 2015-2022 Redistributable after installing the UCRT update
5Run sfc /scannow to repair system file integrity

More in Dll Errors

windows-dll-msvcp140-missingMSVCP140.dll Missing — Visual C++ Runtime Error

Error

windows-dll-vcruntime140-missingVCRUNTIME140.dll Missing — Visual C++ Runtime Error

Error

windows-dll-xinput1-3-missingXINPUT1_3.dll Missing — DirectX Runtime Error

Warning

Frequently Asked Questions

It is a system component that provides C runtime functions. Starting with Windows 10, it is built into the OS. Older versions need it installed via Windows Update.