Note: To see what version of Adobe Flash Player you have installed, you can visit the Flash Player Help / Find version page. If this version is current (21), you can stop now.
1. Close all open applications on your desktop/laptop device.
2. To update to current Adobe Flash Player version (21), go to http://get.adobe.com/flashplayer/.
3. UN-CHECK any extra toolbars that are offered. Example: Google Toolbar.
4. Click Install now.
5. Follow on-screen steps to install.
Note: If asked to choose your Update method for future Adobe Flash Player releases, choose Install updates automatically when available (recommended).
Note: If the Adobe Download Manager tells you that the installation failed, click Close Download Manager. Proceed to step 6 anyway. You will likely see that the installation was successful.
6. When the installation completes, you should see the current version of Flash Player displayed on the screen.
Note: The Release Notes for Adobe Flash are here.