Install ASP.NET 4.0 application on Win 2008 64bit server

General information for the business: We run an SMS reminder service
Description of requirements/functionality: Help! I need an ASP.NET 4.0 application (exposed via ASP.NET Web Handler file) installing on a vanilla cloud server. Server is Windows 2008, 64 bit edition, with IIS 7. The basic problem is I have no idea how IIS 7 works, and my attempts to use the application wizard have met with failure 'Invalid application directory.'

I have the same application running on a vanilla 2003 server running IIS6, so there is potential to compare and contrast.

I don't expect you to know how my application works, just to be able to make sure that everything up to the application is working. E.g. IIS permissions are correct, correct application pool is being used, and so on.

I can supply logins for both running and to-be-installed server to successful bidder. It might be that my service needs some tweaks for 64 bit platform, but I can handle that. I just don't know how IIS 7 works.

My preference is for short, concise proposals demonstrating comprehension and relevant experience for the specific problem.
Specific technologies required: ASP.NET 4.0, IIS7, Windows 2008 64bit
OS requirements: Windows
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