I got a free copy of the basic edition of Vault Server 2012 off of the Autodesk website from
here at the beginning of the year. It would appear though that the file is no longer available, possibly due to the release of Vault 2013. I do still have the installer, but I'm guessing it wouldn't be legal to redistribute. Perhaps someone should email Autodesk and ask if the download link is intentionally dead.
My searching has turned up that there is no publicly available edition of Vault 2013. Based on
this, it looks like you need to be a Subscription customer to be able to download it. If your team's school has a tech department that uses Inventor, I would check to see if they happen to have that access.
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