What OS are you running? I had problems on Mac OS just now. If you are too, it kept prompting me to quite Safari. It wasn't running. What I ended up doing was quiting the installer. It will launch Safari again to report your experiance. Quit Safari (don't merely close the active Safari window leaving the Safari process running).
I went to Activity Montitor (search for it in Spotlight, or it's in your Applications/Utilities folder. Change the few from Windowed Processes to All Processes and locate or just search in Activity Monitor for processes called WebKitPlugInAgent and/or WebProcess and quit either or both that may be running. The installation completed after that.
If you're stuck with a prompt to quite Dashboard though before Safari, do the same thing as above for Safari, and search for any process named Dashboard and quit it. It will immediately open a new process of the same name, but that's OK, it will then allow the Adobe installer to move on.
If you're not on Mac OS, look at these KB support articles:
Message was edited by: neverman.zero
I'm running Windows 7.
Can't thank you enough for the helpful information. I was about to start tearing my hair out. It was apparently the Active-X Control that was causing the problem. You the man! (or woman?)