You could try to open a support ticket. I think not many people already did the transition to OpenJDK 8.
Regards,
Ronald
As of Mendix 7.23.3, we check two locations in the registry to see whether OpenJDK or Oracle is installed. If neither of them is there, we install OpenJDK. But I don’t think the installation failing has to do with the switch to OpenJDK.
Perhaps you can try and get an installation log by passing a parameter to the installer from the command-line. For example:
C:\Users\USERNAME\Downloads> Mendix-7.23.3.48173-Setup.exe /exelog installation.log
Hopefully that will give some clarity.