I use the following code to create a app pool:
var metabasePath = string.Format(@\"IIS://{0}/W3SVC/AppPools\", serverName);
DirectoryEntry newpool;
DirectoryEntr
I see from the tags you're using IIS7. Unless you absolutely have to, don't use the IIS6 compatibility components. Your preferred approach should be to use the Microsoft.Web.Administration managed API.
To create an application pool using this and set the .NET Framework version to 4.0, do this:
using Microsoft.Web.Administration;
...
using(ServerManager serverManager = new ServerManager())
{
ApplicationPool newPool = serverManager.ApplicationPools.Add("MyNewPool");
newPool.ManagedRuntimeVersion = "v4.0";
serverManager.CommitChanges();
}
You should add a reference to Microsoft.Web.Administration.dll
which can be found in:
%SYSTEMROOT%\System32\InetSrv
The other answers are better in your particular scenario, but in general keep in mind that you can use the appcmd tool to do this: https://technet.microsoft.com/en-us/library/cc731784%28v=ws.10%29.aspx. Specifically:
appcmd add apppool /name: string /managedRuntimeVersion: string /managedPipelineMode: Integrated | Classic
newpool.Properties["ManagedRuntimeVersion"].Value = "v4.0";
Will do the same thing as the Microsoft.Web.Administration.dll but using DirectoryEntry
Also
newPool.InvokeSet("ManagedPipelineMode", new object[] { 0 });
Will switch to integrated or classic pipeline mode using DirectoryEntry.