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I do not claim this as my find, i just found this and thought some may find it useful.
Enjoy!
To try it out, first close all the IM windows you have open. Then click the “Turn ON tabs in Yahoo! Messenger” link below. When the download window appears, click the “Run” button and follow the on-screen instructions to install it. The next time you’re in two or more IM conversations at the same time, you’ll see the tabs in action. To close a tab, just right click on it.
Download the reg files
Turn ON tabs in Yahoo! Messenger 8.1 Turn OFF tabs in Yahoo! Messenger 8.1
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Update utility for Yahoo Messenger Tabbed IM windows
Problems with the current tabbed IM chat windows for Yahoo Messenger make it almost impossible to use:
You have to have a IM window open to receive new IM messages
You dont know which tab has sent you a new message
you dont know if any new messages have been received if the Tab IM window has focus
You have to resize the window each time a new message tab is opened
Changing and closing tabs does not change the window title
You have to run a reg file to enable/disable each time
WackyB-IMTab-Fix solves all these problems:
Enables tabbed IM windows when you start WackyB-IMTabFix
Disables tabbed IM windows when you close
New IM windows are displayed correctly
Notification is given in window title when new message received
Sound alert with new IM from hidden tab
Changing tabs updates window title
First IM received displays correctly ** IF YOU DONT RUN THIS UTILITY AND IF YOU DO NOT HAVE A TABBED IM WINDOW OPEN YOU WILL NOT RECEIVE NEW IM MESSAGES! **
As you can probably guess it not only makes improvements on the TabbedIM features but also adds an Auto Reply message
1)
Download here: (1.8mb)
* Some users may receive an error/warning during install, simply click 'OK' to ignore this.
2) Install and run from your start menu.
Note: Ensure ALL IM windows are closed BEFORE starting WackyB-TabIM-Fix
WackyB-TabIM-Fix runs in the background taking care of your tabs, to exit click the icon in your system tray
ScreenShot shows window title matches IM tab :
Shown here is notification of new IM from a hidden tab (Active tab is 'Stickercam', message from hidden tab 'bourbon bee' ) :
It even works with Windows Vista.