How to Fix and Play Legacy Unity Player Games

Don’t you hate it when websites you used to love get old and you can’t use them anymore? A good example is the TRON fictional movie game “Space Paranoids.” If you can find a site that still hosts it, you can’t play the special game replica of Space Paranoids that they made for the Flynn’s Arcade live launch event of 2010 film TRON Legacy.


You can’t play it because it is seven years old, and sites are not maintained which is a shame. But more crucially, the Unity Player has been upgraded in the intervening years to make old games effectively unplayable.

But say, for example, it was your mission to make your own Space Paranoids arcade machine. Or what if you wanted to play any other old Unity 3D web game you used to love which is no longer available?

In this article we look at how to play old online Unity games which have passed their “sell by” date.

Finding the parts

Using the Space Paranoids game is a good example of this idea because not only is it an iconic and fabulous game which has been made obsolete by updates (and it would be a pity if it died), but it also exemplifies the kinds of problems you face in such a project.

In order to make this game playable again you need two things:

  1. the original Unity3D file containing the game data which was originally hosted on the web
  2. a Unity Web Player which is capable of running the old file and playing it

Finding the game file itself is a bit of a pickle but not impossible. Here Google is your friend. Search for “Space Paranoids Unity3d” and follow the links. Hunting around, there were a few locations for the original game, some official but abandoned, some not so official. This non-official one is an online gaming site, and along with hosting the (now broken) game, they helpfully provide a Download button for you to obtain the original Unity3D binary.

Note: if the website you find is not so forgiving, then you should examine the source code of the page and identify where the Unity3D file is stored, then pull out that URL and use it to download the file.

If you try to play the game on any site which hosts it and are running Firefox, you are asked to activate the Unity Web Player.


When you try you get the following message: “The webplayer cannot load the specified game content. The game you are trying to play was built with Unity 2. The current Unity Web Player only supports running games built with Unity 3 or newer.


A little research indicates a very interesting fact, that the Unity 3.4 Player was actually the last one to support 2.x games. So the mission now becomes where can you get a legacy 3.4 version of the Unity Player?

Fortunately we discovered there is a legit and safe way to get the 3.4 web player. The Unity Download Archive on the Unity site has a copy of the full install of Unity 3.4 which also contains the Web Player.



Install the Unity Editor but don’t bother running it as you won’t need it. Just look inside the “C:\Program Files (x86)\Unity\Editor” directory and locate the EXE file called “UnityWebPlayerDevelopment.exe” and run it. This will install the Unity 3.4 web player onto your machine. After you have installed the player, you can uninstall the Unity Editor but save the player installer somewhere safe first.


Once you’ve done that you’ve finished. Now when you run the Unity3D file it opens your browser and plays the game. For added value, try making your browser full screen, and then when you run the game it will fill your screen.



Caution Firefox users: Just as we were preparing this article, version 52.0 of Firefox came out and cut off support for NPAPI plugins. Luckily, Mozilla took pity on anyone using NPAPI plugins and extended support until 2018, provided you are using a special version. In order for this to work, you need to download the special Firefox ESR or extended support release of Firefox 52.0 which you can get from here.


There is very little on the Internet which is truly “dead” or “abandoned” that you can’t resurrect in some way with a bit of detective work and persistence. Okay, so you can’t play any new Unity3D web games on this new machine you made now that it is a Unity 3.4 machine, but if you are intending to build a full-sized Space Paranoids cabinet around the computer, this shouldn’t be a problem.

If you have any comments or questions, please leave them in the comments section below.

Image credit: TRON control panel

Phil South
Phil South

Phil South has been writing about tech subjects for over 30 years. Starting out with Your Sinclair magazine in the 80s, and then MacUser and Computer Shopper. He's designed user interfaces for groundbreaking music software, been the technical editor on film making and visual effects books for Elsevier, and helped create the MTE YouTube Channel. He lives and works in South Wales, UK.

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