Having updated to the latest Firefox version for a 32 bit system on Windows Vista, I'm experiencing the same launch problems for Adobe's Flash Player as with the Shockwave programs in all current and previous Firefox versions. Interestingly, I can launch a previously saved version of Flash (Version 17) and it will "Run", but not the more recent versions (23-25). All I see is the hour glass for about 10-20 seconds and then nothing each and every time. Just recently, I received a permission error, and so I right clicked the "Run as Administrator", and still nothing. I then disengaged my firewall and all other security, and re-downloaded. Nothing again. Of course, I even shut down the browser and tried launching - but still nothing. All other executable programs work except for these. Could it be the communications between Adobe and my computer? Should I download the file from a different website? All comments are appreciated.
You're title is a bit confusing, as it eludes to Flash Player content, but reading through the post, it sounds like you're referring to the installer itself not launching.
If the former (Flash content not loading), post a direct link to the content that is not loading.
If the latter (installer not launching), it's possible your Windows Vista machine does not support SHA256 digital signatures. If you're Vista system has Service Pack 2 installed, please see https://support.microsoft.com/en-us/kb/2763674 for assistance. If you have Vista SP1 or lower, try using the offline installer posted at the bottom of the Installation problems | Flash Player | Windows 7 and earlier page in the 'Still having problems' section, although there is no guarantee it'll work.
Shockwave Player is a different product. It may be experiencing the same issue. Please post your Shockwave Player query to the Adobe Shockwave Player forum for assistane.