today I have upgraded em client it gives message "api-ms-win-crt-stringl1-1-0.dll is missing. how to rectrify

Same here with the last two or three builds, check:

I can fix it by installing the latest Visual C++:

https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

But it should be included in the setup.