Thank you, these are very useful links.

Win32::SysTray I could put to work:

use strict;
        use Win32::SysTray;
        
        my $tray = new Win32::SysTray (
                'icon' => '/Icons/Application.ico',
                'single' => 1,
        ) or exit 0;
        
        $tray->setMenu (
                "> &Test" => sub { print "Hello from the Tray\n"; },
                ">-"      => 0,
                "> E&xit" => sub { return -1 },
        ); 
        
        $tray->runApplication;
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Also I have found an example where with Win32::GUI the entire taskbar can be hidden:

use Win32::GUI;

my $taskbar = Win32::GUI::FindWindow("Shell_TrayWnd", "");

Win32::GUI::Hide($taskbar);

sleep(3);

Win32::GUI::Show($taskbar);
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Since building Gtk2 may be beyond my capabilities on the other hand Win32::GUI is already available and seems to have similar capabilities I ask:

Is it possible by using pure Win32::GUI to switch off the taskbar icon for an app?

update: build-gtk-glib-post.PL fails:

Can't open gtk_bundle/lib/pkgconfig/libglade-2.0.pc: No such file or d
+irectory.
Error GETing http://www.gtk.org/download-windows.html: Not Found at gt
+kinst.pl line 113
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