you could do it using the shell external if on a mac-- not sure how to do it on windows

Hi Floating Point, at first many thanks for your prompt response. Although I am a max veteran and als ancient Mac user, I have to admit that my experience with the terminal (and I understand the shell is or is part of it) is very little, also I never used any shell commands knowingly. May I ask you for some help in that, if you can spend a moment? It looks like you are experienced with these things. As I said what I wish to do is opening another app from within a max patch. Everything following this will be happening as usual. It would be great, if you could supply me with an example patch? Many thanks HPK PS: I got the shell.mxo by bernstein

actually there's a windows version too in this download (first post): https://cycling74.com/forums/shell-2013

thank you again, but I really have no knowledge about all these system language. So many thanks for your effort, but I need to find someone who could write me a patch that would allow to select a file in Max and send it to another app for external editing.

Many thanks anyhow and have a good day. HPK

Try this for a built-in Max solution:

Thank you Jean-Francois Charles for the patch, only it always opens the file in iTunes. Where do put the name of the app I want to use. In the message box appears only the complete of my soundfile and when I click it, it opens in iTunes. Sorry for bothering, but it looks its close to what I was looking for

Thanks again HPK

It will open the files with the "default application for this type of file" in your system. If you want to open a sound file with another application, you have to make it the default on your system. On a Mac, that would be select the file, Get Info, then in the "Open with..." section, choose the app you want. Then click "Change All..." Or something like this. I don't have experience on Windows, but that shouldn't be that different.

IT WORKS !!!! Many Thanks. All the best HPK