The Adobe Flash add-on might not work in Windows Internet Explorer if you're using the 64-bit edition of Internet Explorer or have disabled the add-on. ActiveX Filtering in Internet Explorer 9 can also prevent the add-on from working.
Here are some things to try:
Use the 32-bit edition of Internet Explorer. If you have installed either Internet Explorer 8 or Internet Explorer 9, both a 32-bit and a 64-bit edition of the browser are available on your computer.
Open Internet Explorer, and then do one of the following:
In Internet Explorer 8, click the Help menu, and then click About Internet Explorer.
If you're using the 64-bit edition of Internet Explorer, 64-bit Edition will appear to the right of the version number. If you're using the 32-bit edition, nothing will appear to the right of the version number.
Don't click either Internet Explorer (64-bit) or Internet Explorer (No Add-ons).
To ensure that you use only the 32-bit edition in the future, you can pin it to your taskbar. For more information, see Pin a program to the taskbar.
Enable the add-on in the Manage Add-on dialog box. For more information, see
How to manage add-ons in Internet Explorer 9.
In Internet Explorer 9, turn off ActiveX Filtering. For more information, see How to use Tracking Protection and ActiveX Filtering.