Thanks so much for the quick response Robert. We have a process where a user selects an entry from a particular folder then selects a custom button that launches a program. We then want that program to open an entry in another folder in a new MainWindow so the original MainWindow remains unchanged. We don't want to require the user to manually open a new window. I attached a screen shot.

Interesting, I can see the usefulness. The closest thing available is to call mainWindow.LaunchSearch with with Query={LF:LOOKIN="\the folder to show", SUBFOLDERS=0}, NewWindow=true, LeftPaneDisplay=LeftPane.Search. This will open a new window with the contents of that folder. I have filed a feature request for opening a new MainWindow directly.

You could also use CAT and/or Win32API to open a new LFDesktop window to the folder you want.

Thanks Bert!