The AppCRT and DesktopCRT libraries have been recombined into a single library, which is named the Universal CRT.
Get the Universal CRT dll file at the ucrtbase.dll file page.
For the debug version of the Universal CRT dll file go to the ucrtbased.dll file page.
If you have a program requesting AppCRT or DesktopCRT dll files, check for an updated version of that program
Read more about the UniversalCRT at the Microsoft Visual C++ Team Blog