Can't start WinForms project because Form is a type

I have a very small VS2008 Winforms project that will not start.

When I attempt to start debugging the project, I get the message:

'<form>' is a type in '<project>' and cannot be used in an expression.

From the file .Designer.vb.

The probl开发者_运维问答em is that is indeed a form. If I create a new WinForm and set the startup object to the new form, I get the same message.

When I attempt to check the "Enable application framework" checkbox in the Project properties, I get the message "Startup object must be a form when 'Enable application framework' is checked.

I've tried creating a new project and moving all the code and designer objects to a new form file in the new project, and same result.

Other projects on the same computer run fine.

Any suggestions?

Thanks!

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Turns out that the problem was that I didn't have a New() function with no parameters. This is required for VS to see the class as a form.