I have ASP.NET web services and ASP.NET web application running on .NET framework 1.1 hosted on a Windows Server 2003 IIS 6 machine.

I have a new application requiring on .NET 4. Until I installed ASP.NET framework 4.0, it was working fine.

Now my .NET framework 1.1 applications have failed.

How can you configure an IIS 6 instance to run 2+ applications each respectively requiring different versions of the .NET framework?

migrated from stackoverflow.com Jun 28 '11 at 17:56

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You have to create at least two separate application pools - for two different frameworks. Then assign each application to run in the appropriate pool.

These links may help too:



  • how to assign frameworks for two different app pools, i did not see any where assigning frame work in create application pool in iis6. i can see this in iis 7 – Pradeep Jun 28 '11 at 16:11
  • this info is not sufficient – Pradeep Jun 28 '11 at 16:12
  • sorry, let me clarify. you just set up separate application pools, you don't specify framework version for app pool. but in your web application you specify framework version in ASP.NET tab. – Kon Jun 28 '11 at 16:14

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