Open the Activity Monitor. Find CS5ServiceManager in the List of Process Names and click it to highlight. Then, click on the Quit Process (stop sign icon). It will ask if you want to Force Quit. Select Yes. Then, hit the Retry button.
thank you Jim... that worked perfectly!!!
You're very welcome. Remember this when you run some other Adobe updaters, too. DynamicLinkManager needs to be force quit pretty often as well. I'm glad it worked for you.
You can also reboot to quit those processes, but that's not necessary when you know about this tip.