I've written an app that connects to websites APIs and does some things there. It is a app written in C#, .NET 3.5 on a XP OS.
Now I have a problem. Some people reported that this application hangs on Vista, and not on the more new version of Windows (what was the name?)
So I do not have Vista and do not have money to buy this system only to test this one, freeware application. Is there any other way to test my app if it is valid for Vista or is there other way to make sure it will be working? I'm in a blind spot here and do not know what to do next.
Update: I use Visual C# Express 2008