Faq/General/api-ms-win-*.dll is missing

On Windows versions prior to Windows 10, sometimes after installing LibreOffice, launching it results in an error message like this:

The program can't start because api-ms-win-crt-runtime-l1-1-0.dll is missing from your computer. Try reinstalling the program to fix this problem.

The missing DLL may vary; usually it's  or.

The reason for the error is that LibreOffice depends on a system component, MS UCRT, to be present on the system. LibreOffice installer includes the component, and tries to install it when installing LibreOffice. The component installation requires Windows Update service to be accessible (LibreOffice knows how to temporarily enable the service if disabled by usual means, but not when advanced methods to disable are used, e.g. associating it with Guest account). Also, in older versions of LibreOffice, a check was made if UCRT is already present on the system prior to installing, and its installation was skipped when it was detected.

So, scenarios where installing LibreOffice may skip installation of this required component include:


 * Cases where Windows Update service is disabled using some advanced methods.
 * For some older LibreOffice versions, cases when MS UCRT is 'partially' present on system (improperly installed by another application) - this case is associated with  message. This is the case for Avast antivirus pre-installed. In later LibreOffice versions, we decided to not check for the component presence for this reason, and now the installer tries to install the component unconditionally (repairing broken installation cases).

In these cases, installer should issue a warning, like this:



In all such cases, to fix the problem, one needs to install the component manually, using a relevant package for the OS available at the Microsoft site linked above. If the Windows Update service is disabled, one needs to enable it temporarily.