May I know the following info for better investigation:
Did you select the Window version the moment you about to download Quartus?,
Did you fulfill the requirement for installation like window version,memory, disk space etc.
Refer to this link and click system requirement for verification
Here a workaround for you, try to re-download the Quartus for both combine or separate package and install it again by disabling firewall or antivirus or window defender or all of that for a moment.