Vista (32bit) go to C:\Windows\System32\Macromed folder
Vista(64bit) go to C:\Windows\SysWOW64\Macromed folder
Open the folder and right click on 'FlashUtil9b.exe', then left click 'Run
as Administrator.' The Flash Player installer should now start and once it
completes, Flash Player should work and appear on the uninstall or change
program list.
This issue is related to how Windows Vista's security features prevent
applications from changing registry settings (even if you are logged in as
an administrator) you must explicitly allow programs to make certain changes to
the registry.
I know it's annoying and this is one of the things about Vista I don't like.
AMD Athlon 64 X2 4400+ OC 2.7ghz
4GB Dual Channel DDR 3200
Nvidia 7900GT
SATA II 2x 300gig 7200rpm 16mb cache RAID-0+1
Gigabyte Nforce 4 SLI