you need to access Yahoo messenger for this, see this link for more info **broken link removed**.
Also search in the internet for VB applications using serial port, there are many projects that can give you an idea.
Have you made the hardware for the project. Your hardware would consist of a mcu connected to a MAX 232 level converter (for RS 232 communications) and several relays to control appliances..
Note: As the device is not standalone (ie: the device will be connected to a PC or a laptop that has access to the internet) , you can probably use a parallel port instead of serial port, this will eliminate the micro-controller, and the hardware will just consist of a opto-isolators, and relays. This will make your project less complicated and with programmming effort required only for developing the Yahoo messenger interface and the parallel port interface using VB.
thanks
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