Excel - How to fix the “api-ms-win-crt-runtime-l1-1.0.dll is missing” error for Excel:
Error message in Excel 2016 - Installation:The program can't start because api-ms-win-crt-runtime-l1-1.0.dll is missing from your computer...

How to fix the “api-ms-win-crt-runtime-l1-1.0.dll is missing” error for Excel 2016:

0.Close Excel

1.Try to reinstalling or repair the office (Excel) to fix this problem"

2.Try to Install all pending Windows Updates Go to Start > Control Panel > Windows Update Check for updates and install all pending updates, then restart the computer.

3.My Recomended solution:

Go to...
-Update for Universal C Runtime in Windows:
https://support.microsoft.com/en-us/kb/2999226
Select the update for you windows version (32 or 64 bits)..and finally restarting your Excel.