Windows Media Player 11 SDK BUTTONELEMENT.upToolTip
The upToolTip attribute specifies or retrieves the ToolTip text that appears when the mouse is over the BUTTONELEMENT and the BUTTONELEMENT is in the up state.
This attribute is a read/write String with a default value of "" (empty string) with a maximum length of 1024 characters.
See the mappingColor attribute for a sample illustrating the use of this attribute.
When this attribute is set to "" (empty string), no ToolTip is displayed.
Windows Media Player version 7.0 or later.