IntelliTrace is an new features of Visual Studio 2010 Ultimate Edition. By default IntelliTrace is enabled . During debugging in Visual Studio, IntelliTrace works in the background and collect debugging information automatically and stored them in IntelliTrace Log File (. iTrace File ) . You can use the log file at any point of time to see what happened exactly at background during your live debugging. One of most draw back of IntelliTrace was to support only 32bit Application. So, If you have are running your application in a 64bit Application, you have to debug your application in 32 bit mode to deal with IntelliTrace. If you are trying to debug an 64 bit application using IntelliTrace you will get below message in IntelliTrace Window.