By default, IIS uses a new ASP.NET runtime mode, which supports the next generation integration between ASP.NET and IIS. For the most part, existing ASP.NET applications will work fine in this mode, but there are certain cases where they may not.
In one particular case, you will get an "Application must be migrated" error message, and will be presented with several options around migrating the application, or moving it to a backwards compatible mode. This is described in detail here: http://www.iis.net/default.aspx?tabid=2&subtabid=25&i=928&p=2.
There are two known issues with the migration functionality provided via the AppCmd command line tool:
1) When migrating the <httpModules> configuration section, the module <add> elements in the resulting <modules> configuration section will contain a preCondition="ManagedHandler" attribute. The value of this attribute needs to be changed to "managedHandler" in order to succesfully enable these modules to execute.
2) When the web.config of the application being migrated contains an XML namespace declaration, such as <?xml version="1.0"?>, migration may fail. We are investigating this issue. The current workaround is to remove this declaration, perform the migration, and return the declaration to the configuration file. For more information on this workaround, see the original problem post here - http://www.holliday.com.au/blog/iis7-direct-net-integration-mode-preferred.html.
We will be posting a list of other known ASP.NET issues soon.
This posting is provided "AS IS" with no warranties, and confers no rights.