Now I know why "Application Pool" is a selection

I never tried to run two different version of APS.Net (1.1 and 2.0) on the same box, thus when I do such thing in the production box today, I saw something funny like this when I tried to access the ASP.Net 2.0 site that I deployed:

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Server Application Unavailable

The web application you are attempting to access on this web server is currently unavailable. Please hit the "Refresh" button in your web browser to retry your request.

Administrator Note: An error message detailing the cause of this specific request failure can be found in the application event log of the web server. Please review this log entry to discover what caused this error to occur.
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So I followed the instruction and check the Application section of Event Log on the web server. Here's the message I got:


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It is not possible to run two different versions of ASP.NET in the same IIS process. Please use the IIS Administration Tool to reconfigure your server to run the application in a separate process.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
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I see! And the solution is so simple! I went to MMC, right click on Application Pool section under IIS, and select [New][Application Pool ...] . I picked the "Use default setting" one and clicked OK. Finally I went to my web app and set the Application Pool of my web app to use the newly created Application Pool. Result? A successful ASP.Net 2.0 deployment.