When deploying a website or a web service using Visual Studio 2010 we can use a new deployment functionality called Build Deployment Package; this builds a zip file that you can import in IIS. The default location of zip is at ProjectFolder\obj\Debug\Package\.
However in IIS Manager, the default installation doesn’t include option to import our package, additional components need to be installed called Web Deploy (download). After installing the add-on you should be able to see the import option in IIS.
From time to time I see this problem reoccurring, suppose you correctly setup an SQL Login for a certain account and when you tried to login it throws: Login failed for ‘RPAULO_WebUser’ (Microsoft SQL Server, Error: 18456) you might want to check whether the sql server supports mixed mode by going to SQL Server Properties of the server (connect via RDP).
Note that updating the settings would require a service restart to take effect.