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Why did I get the error "A project with an output type of class library cannot be started directly" with the ASP.NET SDK?

You got an error message - "A project with an output type of class library cannot be started directly."

This error occurred because the ASP.NET samples included with the SDK were built as a Class library and not an ASP.NET web application. You can't run the sample in debug mode and step through it as is.

Create your own ASP.NET web application referencing paypal_base.dll if you want the ability to step through your solution in debug mode. You can look to the code in PayPalAPI.cs to see how to use the SDK (paypal_base.dll) to make an API call.
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