Visual Studio 2010 fails to show the design view of an aspx-page

This post is about solving the issue with Visual Studio 2010 failing to show the design view of an .aspx-page. Luckily, it's an easy and pretty classical fix.

Symptoms

Whilst trying to view or edit an aspx-page in design mode within Visual Studio 2010, the window is just plain empty and there's little you can do about it - selecting view markup or hitting F7 may not do anything, and restarting the Visual Studio doesn't help.

Solution

The Design view requires a connection to the SharePoint site where you'll be deploying the solution (or rather, any site). Set the Site URL property in the project settings:

Then close the aspx page and reopen it, and it should work!

Have another workaround? Let me know in the comments section!