I am using Power PC Macs, and therefore I am limited in the software that can run, so I am trying to install the most up-to-date version of Flash player I can, but it is not installing correctly. I get an error message in the middle of the install, so I go back to square one. The weird thing is that I tried to update my flash players on both computers, because I was getting error messages telling me they weren't up to date, so I removed what I was using on both, and the reinstall worked on the Power G4 laptop, but won't on the Mini.
I thought about going into my backup, but don't really know how to use it.
Please see this FAQ for Flash Player on PPC systems.