OK, so I downloaded the latest eLicenser program and installed it after installing Cubase Pro 9 and I get the error “The program can’t start because api-ms-win-crt-runtime-l1-1-0.dll is not on your computer”.
I checked and that file is located 3 times on this computer!
I have uninstalled and reinstalled several times, what do I need to do to get this working please!
Did you download the latest eLicenser version from the Steinberg website or did you use the one that came with CB9? The version on the website is newer and it did help me fix some problems. Not the specific problem you described but, it did help me (and a few others who posted issues). So download the web version if you didn’t already.
Regards 
I’m having the same problem. I did in fact download the eLicenser from their website. Still no luck to fix this. Any suggestions? I’m running Windows Pro 64 bit. I purchased the upgrade for Pro 9 this morning and I’m still dealing with this…
Install all your Windows updates, if that doesn’t help install this:
https://download.microsoft.com/download/C/E/5/CE514EAE-78A8-4381-86E8-29108D78DBD4/VC_redist.x64.exe
…still no luck… HELP!
I found another post where someone solved this and it worked for me. I uninstalled the eLicenser program in the control panel. Then I went into my old Cubase 8.5 folder and installed the eLicenser program from that folder. That installed correctly and then I did the maintenance update and it updated everything properly.
When I went back to the Cubase Pro 9 it allowed me to enter the new Product ID code and register Cubase Pro 9. I hope this helps.