Error: The installation manager encountered an error when creating this registry key
Solidworks System Requirements says versions earlier than 2014 SP1 aren't certified to work on Windows 8.1.
This should not stop you; be sure to install as an administrator of the machine you're on (read more about it in Windows help you can usually RMB on the executable and click "run as administrator") and also, like win7, Win8 (I'm on Win8.1) has "Compatibility mode" to run programs as if they were on previous versions of windows.
I'm not entirely certain about this but when you run the SW install, first make sure you run it as administrator, and second, before you launch it RMB>properties and change the compatibility mode to Win7.
Just had to install 2011 on my laptop and was going through hoops putting VMware with Win 7 on my Mac side; but not enough room left from the bootcamp partition to do it.
Installed it instead on Win 8.1 running via bootcamp, and works like a charm setting the Win 7 compatibility on installation.
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