problem moving from VS2010 to VS2008

Hello,

I have web application developed in VS2010. Now I need to make some changes but in VS2008 (why?to long reason to explain about some old drivers, has to be like this). I created new web page, and when I try to copy and paste the default.aspx and default.aspx.cs, when I build, I'm gerring following error:

Error 7 Could not load type '_Default'.

Please help