Instructions on how to install VirtualBox 4.3.20:
1.) Click here to open link .
2.) Click on download icon.
3.) Save the file on your Desktop for the time being.
4.) Click on [Run] button or just double click the downloaded file.
5.) Click [Next] button.
6.) Click [Next] button again.
7.) Click [Next] button again for the last time.
8.) Click [Yes] button to continue.
9.) Click [Install] button to start installing.
10.) When a pop-up prompt appear, click on [Install] again.
11.) Click on [Finish] button.
12.) (VirtualBox is ready to use).
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