I made some icons a while ago, representing a signed out Windows Messenger, a signed out MSN Messenger, and a transparent box (when in boss protection, it shows the taskbar colour like nothing is there - although you'll see a gap, of course). You can
download these icons here.
At the time I made those icons there was no way of extracting the icon by simply entering a file path in Messenger Plus!'s Boss Protection option dialog window. I think it's still not possible to simply enter a file path there. The files are indeed in the msnmsgr.exe executable, but Messenger Plus! can only extract icons from ICO and DLL files. Simply using these files is by far the easiest solution
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