Doodle IMvironment:
- Open main window of your yahoo messenger.
- Look for a gray icon
, any user has this icon next to his name means he is offline or invisible. - Double click on any username that has this icon, it opens a new window called chat window. Type something or just buzz it and then quickly enough proceed to the next step.
- Click IMVironment button, select See all IMVironments, then select Yahoo! Tools or Interactive Fun, and click on Doodle so that you open Doodle utility.
- Wait until Doodle Window loads and see what of the following happens:
- If the user is really offline then Doodle Window will show this message: "waiting for your friend to load Doodle"
- If the user is online but in invisible mode the Doodle Window will show a blank screen. Keep in mind that you may need to wait for several seconds in order to load.
Thats it!!!
A very simple way to find if your buddy is foolinh you saying he is offline while he is in invisible mode. 
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