Adobe Flash Player update won’t install 10.3.181.26

8/9/2011 – If you’re having trouble installing Adobe Flash and getting error: Corrupt Content From Reliable Source, then click here

Rebooted a machine today and when I logged in as Admin it tried to update the Adobe Flash player from 10.3.181.14 to the latest version 10.3.181.26 and failed to update.

So I tried installing from their website through the Adobe Download Manager, but that didn’t work either, just errored out.  Lots of troubleshooting later, I figured out a way to time it so that the update installs:

1. Open Internet Explorer and goto http://get.adobe.com/flashplayer
2. Either check or uncheck the Google toolbar addon and then click DOWNLOAD NOW button.
3. When it prompts to install the Adobe Download Manager, allow it to install and  it will bring up the status window where you can see the download/install progress of the Flash Player update.
4. As that is downloading (depends on network speed) you should see the regular Adobe Flash Player update window come up and ask you to install the update. 
5. When that appears, you need to very quickly close the Download Manager (answer Yes when it asks you if you’re sure you want to quit).
6. Then use the regular Flash updater program to install the latest update.
7. Check the Flash Player link from the Control Panel and click on Advanced tab to see which ActiveX version is installed.  Should be the latest (10.3.181.26 as of this posting).