In the task bar a balloon with "MTP device has been found" is coming. How to stop this?

Start --> Right Click
Select Properties --> Select Properties
Select Taskbar --> Click Customise box
Click "Show hardware devices" (Some times you may see 'No title'. Select that)
Select "hide when inactive" (on the right)
Change it to "always hide"

This will allow you to use 'Add New Hardware' in Control Panel.

"always hide." This will allow you to use add new hardware, you can then delete the devices

To know what is a MTP device? click here.

Click here to know what is MTP?

My taskbar says a "MTP device has been found". What is this?

Devices like Mobile Phones & Portable Audio/video Players (with USB connectivity) are called MTP devices.

Did you connect 'Mobile Phone' or any 'Portable Audio/Video Player" in your USB Port?
If yes, you will get this balloon in Windows Task Bar.

Upgrade Windows Media Player to ver 10 or higher to stop this 'task bar balloon' and install MTP (Media Transfer Protocol). Click here to know what is MTP

What is PTP?

PTP or Picture Transfer Protocol is used in windows based systems to download pictures from digital cameras. Particularly useful when handling media objects larger than 4GB and streaming videos.

Both Microsoft and Mac have PTP as inbuilt. Linux & open source has many supporting libraries.