Please find below the technical specifications for OIV 4.0, 4.1 and 4.2

Platform Memory Processor Speed Operating System Java
PC 512MB required1GB recommended 1.5GHz required3GHz recommended Windows Vista
Windows 8, Windows 10
5+
Mac OS X 256MB required1GB recommended 800 MHz required1.2 GHz recommended 10.7 (Lion)
10.8 (Mountain Lion)
10.9 (Mavericks)
10.10 (Yosemite)
5+

OIV is not compatible with Chromebooks and iPads.

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The OIV installation file includes Java 6. Machines with 32-bit newer versions of Java will not be asked to install version 6, unless the computer has a 64-bit version.

If you have installed and are running OS Sierra version 10.12, you will need to install Legacy Java 6 to launch and use OIV. If you are not alerted to this when opening OIV, you can find the download here: https://support.apple.com/kb/DL1572?locale=en_US