>Robert,
>
>You also have to create different actions for the application to perform on a file. If you just need to open it, create an action called "Open" and have the value of the action set to something like "C:\Program Files\MyAppFolder\MyApp.EXE %1". For instance, notepad has the "open" action set to "C:\WINNT\system32\NOTEPAD.EXE %1" (at least on my machine). You can view these settings in "Advanced" dialog in Tools/Options/Folder Settings/File Types in explorer.
>

The right way to do this is to create a correct set of registry keys in HKEY_CLASSES_ROOT for the file extension and the application, and create Shell actions for the application under that key that trigger various command lines. This is effectively what you're going in the Explorer dialog; this can be done programmatically. A little sniffing around in the HKEY_CLASSES_ROOT hive of the registry would probably be instructive.

>Hope this helps
>
>>Hello,
>>I have an application that can open different files with different extensions.
>>Examples: .rte .ext .pra .prd .inp etc.…
>>Usually I open a file depending on its extension. I want that the user could open his own files by double clicking on each of them, alike MS Word file or txt file.
>>In my windows OS I assigned the extension .rte and .ext to my application. So when I click on one of these files, my application opens but not the file. What I have to do to open the file as well? Please Help.
>>Regards
>>Robert