An error occurs when more than one version of ASP.NET is configured to run in the same process. Different versions of the .NET Framework and runtime cannot coexist in the same process. Therefore, an ASP.NET application that uses a particular version of the runtime must not share a process with an application that uses a different version. This problem commonly occurs when two or more applications are mapped to different versions of ASP.NET, but share the same application pool.
It is not possible to run different versions of ASP.NET in the same IIS process. Please use the IIS Administrative Tool to reconfigure your server to run the application in a separate process.
To use application pooling, first make sure IIS isolation mode is disabled. Next, navigate to the desired application in the Internet Information Services (IIS) management console and assign it an application pool. If you want to isolate your application from the existing application pools, create a new pool designation.
Note: The process isolation for each application is configured manually.
To disable isolation mode in IIS:
- Open IIS Manager and expand local computer.
- Right-click the Web Sites folder and click Properties.
- On the Service tab, clear the Run Web service in IIS isolation mode checkbox.
To assign a pool designation to an ASP.NET application in IIS:
- Open IIS Manager and expand local computer.
- Navigate to the folder that contains the ASP.NET application.
- Right-click on the folder and click Properties. The application's Properties dialog box appears.
- On the Directory tab, select the desired pool designation from the Application Pool dropdown list.
To create a pool designation in IIS:
- Open IIS Manager and expand local computer.
- Right-click on the Application Pools folder and select New Application Pool. The Add New Application Pool dialog box appears.
- Enter the new pool designation in the Application Pool text box and then click OK.
Note: Remember to configure Web Suite to use ASP.NET framework. Older version of Web Suite should point to ASP.NET 1.1.