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You can now use or create virtual machines. If you need help doing this see the page Creating Virtual Machines in Linux VMware Workstation.
Before VMware will allow you to actually power up a virtual machine, you need to specify a licence key called a Serial Number. This number was sent to you via email when you accepted the VMware license back when you visited the MIT download site.
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Enter your name in the Name box, MIT in the Company box, and the license key in the Serial Number box.
If you do not set the serial number, the first time you attempt to power up a virtual machine, you will see an alert box that looks like this:
