Does Unity only work on Macs? I tried to download the trial file but I cant get it to run on windows.
Thanks
Welcome to the forum… have a look around. Every other thread here is about Unity coming to Windows shortly 
The main one: http://forum.unity3d.com/viewtopic.php?t=18127
Also our web site front page: http://www.unity3d.com
Give it some time. Unity will be on Windows soon.