Set the Microsoft .NET Framework version in IIS 6

If the Web Server is running IIS 7 then follow the instructions in Set the Microsoft .NET Framework version in IIS 7.

Step 1.       Open the IIS Manager (Start>Run InetMgr.exe)

Step 2.       Select the correct version of the web service and open its Properties.

Step 3.       Select the ASP.NET tab and pick the 4.0.30319 version

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Step 4.       Click Yes to restart, if asked.

Step 5.       Select the Documents tab and tick “Enable default content page” then close the properties