Media Bar in Internet Explorer cannot be used
After you install Windows Media Player 10 on a computer running Windows XP or Windows XP Service Pack 1 (SP1), you can no longer use the Media Bar feature in Internet Explorer. When you try to play content by using the Media Bar, an error message is displayed that incorrectly indicates that the latest version of the Player is not installed on your computer. After you click OK in the message, Internet Explorer will open Windows Media Player 10 and play the content you selected.
To prevent the error message from being displayed every time you try use the Media Bar, do the following:
In Internet Explorer, click Media on the toolbar to open the Media bar.
Click Media Options, point to Settings, and then click Play web media in the bar in order to remove the check mark next to this setting (which indicates that the setting is turned off).
The Media Bar feature for Internet Explorer is not included in Windows XP Service Pack 2 (SP2); therefore, if you install Windows Media Player 10 on a computer running Windows XP SP2, you will not see this error. We recommend that you install Windows XP SP2 because Windows Media Player 10 uses the latest security updates and innovations in the operating system to help protect your computer. For more information about Windows XP SP2