Quick Fix: 2008 R2 api-ms-win-crt-runtime-l1-1-0.dll is missing, not enough storage to process this command.

I have just been through a particularly bad support incident, which I wanted to share in great detail. However confidentially precludes me from doing so.

Anyway it turns out it was caused by a failed Windows Update, not a hardware failure as we first suspected.

Plenty of lessons learned here on how not to handle a ticket, but the takeaway is, if you are facing the errors in the title, try this and reboot:

sfc /scannow

You may be unable to launch anything, except a command prompt so it may be you need to go into safe mode which you can set via BCDedit:

bcdedit /set {current} safeboot network

I wish I had thought to check for failed Windows Updates before I started a restore job.. but you live and learn.