If you don't say what's wrong it's difficult to help you.
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when i click on the first part of the installer a box appears saying
Windows can't open this file:
File: MGSO20Installer.part1.rar
To open this file, windows needs to know what program you want to use to open it. Windows can go online to look it up automatically, or you can manually selct from a list
of programs that are installed on your computer.
Then it asks if you want to find one manually or use the web to find the correct program
EDIT: i need to download WinRAR?