Hello all, I realize that I hold an unpopular position on this, but it *will* come back to haunt us: we need to have a way to warn the user if a second copy of Pharo is launched. Random meltdowns and lost work will result from the current behavior. Let me be more bold: lost work and random corrrupted images *are resulting* from the current behavior; they are either unrecognized, or simply ignored, but it is happening. Is there a way to fix it? On Windows, I recall creating an OS semaphore with a given name and if that exists, bail out before the session even gets going. We would need a cross-platform way to do that (or at least a Linux/Mac way to do it - Windows has a mechanism), and then a place to abort startup early enough to prevent problems. Any ideas? Bill