This error is thrown when Web App could not find the required files, because a supported version of MCR is either not installed or it is not added to Windows PATH system environment variable before any installed version of MATLAB.
To resolve this issue, make sure you have installed correct version of MCR and added the MCR folder location to PATH environment variable before any other MATLAB/MCR folders.
The default location would be-
C:\Program Files\MATLAB\MATLAB Runtime\v94\runtime\win64
Once you change the PATH, Web App Server will pick up the necessary files from MATLAB Compiler and it will run smoothly.
Hope this helps!