McNeel Wiki

Rhino V4 was designed to run under Windows XP, but it can run as originally designed in modern versions of Windows. Here are the limitations and requirements to run Rhino V4 under newer versions of Windows.

• Memory - Your new 64-bit computer system probably came with 16GB of RAM or more. Rhino V4 is a 32-bit application. This means it is limited to using a maximum of only 4GB of RAM no matter how much RAM your new system has.
• Legacy Application - Rhino V4 was released before Microsoft added User Account Control to Windows. To work around this feature, you will need to run Rhino V4 in Windows XP SP3 Compatibility Mode or Windows will block Rhino from saving changes to your toolbars and other settings when Rhino is closed as it was designed to do. Windows Compatibility mode settings are part of the Desktop shortcut properties.
• Low resolution - Your new computer probably is capable of running at much higher screen resolutions than your old Windows XP system. You will need to limit Windows and run it at a lower screen resolution (like 1024 x 768), that was supported back when Rhino V4 was released. If you don't some tools like the Layer panel will be blank and Rhino V4's toolbar icons may be too small to read.

In addition to the new features and capabilities in Rhino V6, to take full advantage of the features of your new 64-bit Windows system, including RAM, display resolution, etc., you should consider upgrading to Rhino V6. Back in January 2007 when Rhino V4 was released, it supported the features of 32-bit Windows XP. Windows and computer hardware have come a long way since then. To take advantage of these new features and capabilities, you will need a version of Rhino designed for it.

Try the free 90-day evaluation license for Rhino V6 and see if you like it better on your new computer.