how does VIsual Studio 2010 decide which projects to start up in a webdev instance?

I have a solution with two web applications/projects. Both start up on F5 but on shift+F5 only one stops forcing me to manually close the webdav of the second one application. I don't want to create marcos to shut down the process and I don't see the properties window with the option in this thread I just see normal properties pages of the project.

So if I don't manually stop the webdev server and I press F5 again I get a message "Unable to start debugging" because the port is fixed on the web app which didn't stop. Note that it says "Unable to start debugging" not "Unable to start debugging in the web dev".

How does VS decide ok let me run this two web applications but if I have two winform apps its smart enough to start just the strat up project ? Thank you

PS: I don't believe it's in the build files, so where is it ? In the loaded environment or someth开发者_开发问答ing ?

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Click on your project in solution explorer that you dont want to start up, and in the properties window set "Always start when debugging" to false. If you don't see the properties window, press F4 or go to View -> Properties Window. I usually set that to false for all projects and then only the project set as the startup project will start.