I had this problem and by looking into the Event Viewer's application log I spotted that if failed because .NET Framework 4.8 was missing. After installing that manually the MP2 installation succeeded.
Hope this might help!
MediaPortal Version: 1.4.0
Description
When mounting a dvd image that has already been watched, the sub menu letting you choose to start from beginning or continue where last left off is thrown behind mediaportal main window, unable to act upon.
Steps to Reproduce:
Select dvd image to...