Add Web Role Project in solution option freezed

I am trying to migrate a small ASP.NET 'web site' (not web application) to Windows Azure. I have add开发者_高级运维ed the website to the solution by Add Existing Project> Selecting the *.sln file. After this, when I right click on the Web Role in Windows Azure, the "Add Web Role Project in solution" is freezed and so, I am not able to create the web role?

Why is the option freezed? What's going wrong in here?

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You have to convert your web site to a web application before you can upload it to Azure.

To do this, follow these instructions - http://msdn.microsoft.com/en-us/library/aa983476(VS.80).aspx