Upgrading Web Forms ASP.Net 3.5 to 4.7

Question

We have a web forms project that is running on ASP.Net 3.5 and we need to upgrade all the way to 4.7. Telerik controls are involved which I know will need to be upgraded as well. This is a large web application and I know there is not quick solution, but trying to figure out how to get started. Does anyone have any recommendations for such a task.

Answer 1

It depends on the CLR for the .Net framework you are using. .Net Framework 2.0, 3.0, and 3.5 uses CLR 2.0 .Net Framework 4, 4.5, and 4.5.1 uses CLR 4.0 CLR 3.0 does not exist An application developed in .Net 2.0 or 3.0 can run in a 3.5 framework because the target CLR is the same

But an application developed in .Net 3.0 will not run in a 4.5 framework because now the target framework is different (CLR 4)

Solution

To configure your application to run on .Net Framework 4 or 4.5:

Create a text file that has the same name as your application, and add the file extension .config. For example, if your application is named abc.exe then your application configuration file must be named abc.exe.config. Add the element as follows to the application configuration file:

`<configuration>
  <startup>
    <supportedRuntime version="version"/>
  </startup>
</configuration>`

Check framework upgrade guidelines here: https://social.msdn.microsoft.com/Forums/vstudio/en-US/d4c6adee-4dd5-435d-a021-4fd9d4c6f7c0/net-framework-upgrade-from-35-to-471?forum=netfxsetup