Unity Web Player

You don't need the web player to watch videos.

 

So, let's have a think. Firstly it's helpful to know the exact OS version and browser version, since sometimes the behaviour of the web player changes according to where it's running. Secondly, it's helpful to post a screenshot of the error. I'm not sure that I have seen "impossible to load Unity Player" as an error in the Unity web player. Maybe visit:

http://unity3d.com/webplayer

Top left of this page should be a message that tells you the version of the web player. I believe that the current version is 4.3.5 or 4.3.6. If you have this, then one of the 3 components you need is installed. If you do not get a version number displayed, then the install hasn't worked correctly.

Next, it's helpful to know if you are on PC or Mac. (Obviously IE users are on PC.) Look for the folders where the web player are installed:

PC: c:/Users/{you}/AppData/LocalLow/Unity/WebPlayer or
PC: c:/Program Files (x86)/Unity/WebPlayer (if you installed with the /AllUsers flag.
Mac: /Library/Internet Plug-Ins/Unity Web Player.plugin

In these folders you should find the Mono and Player components. On a PC, look into the folders called player and mono. These should contain folders, with names like Stable3.x.x and Release3.x.x. In those folders you should have a file called info.plist. So, on my machine, I have

C:\Users\graham\AppData\LocalLow\Unity\WebPlayer\player\Stable3.x.x\info.plist.

When I open that with a text editor, I see:

Code (csharp):

1.     <key>CFBundleVersion</key>
2.     <string>4.2.4f1</string>
3.  

which tells me that this is the 4.2.4f1 player. On a Mac, the folder called /Library/Internet Plug-Ins/Unity Web Player.plugin/Contents/Frameworks will contain two bundles. These contain Info.plist files also, so my ReleaseUnityPlayer3.x.x-i386.bundle has an Info.plist in Contents that tells me it's the 4.3.6f1 player.

If your web player is not working, it could be because your Plugin has not installed correctly, meaning you do not have a folder called loader (PC) or the Unity Web Player.plugin (Mac). Alternatively, the mono and player runtimes might not have been downloaded, or you may have a version which for some reason cannot be used. If you get an error which doesn't appear to come from Unity, then it's possible that your browser is preventing the plugin from running.