The Select Application Server... window is launched when you are creating a new extension and the Show "Select default Application Server for new extension" window property is checked.
The parameters of this window are presented below.
Indicates the application server for the new extension. The possible values are: .NET, J2EE and Both .NET and J2EE.
As soon as possible, the application server should be selected for the template files (The files needed to generate the Extension assembly without any custom code, without any code written by the developer. These files are implicitly generated by Integration Studio in the following operations: Create a new Extension, Update the Extension Source Code, or Compare with Template) generated by Integration Studio. You can change the application server, afterwards, but this might have an impact on the extension definition, since the resources added so far will be excluded from the extension.
Use this as the default and do not ask again
Check-box that indicates whether this window is to be displayed when creating a new extension. If it is un-checked, the value of the Show "Select default Application Server for new extension" window property is also changed. The next time an extension is created, this window is not displayed and the application server will be the one you defined as the default.
Create an Extension | Options Window | Extension Properties