Visual Web Developer Express 2010 runtime launches two web pages

I have an annoying issue with Visual Web Developer Express 2010. When I run my web app wi开发者_StackOverflowth CTRL + F5, VS launches two IE pages of my app. When I run the app using just F5, I get one page of IE.

Is this a bug?

it never happened with me

focus on the aspx (not the code behind page) and press

Green arrow (within the black circle in the image) is equivalent to F5

or the page with magnifier lense (within red circle ) is equivalent to ctrl + F5

hope this is usefull