ok, one more thing to try if you can bear with me.
Try disabling aero theme in vista and try the messenger windows in restored and maximized mode.
My best guess is that Enhancer should treat the window differently if the aero theme is in use.
Does Win7 have the aero theme as well ?
Window Manager is discontinued, for WLM try the new, Enhancer for contact list docking, auto-hide, hide taskbar button, remove button flashing and remember keyboard layout in conversation windows
Messenger Plus! Live Enhancer
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