(1) Use the Adobe Flash uninstaller to remove Flash Player
here
(2) Delete Flash Player files and folders
C:\Windows\SysWOW64\Macromed\Flash
%appdata%\Adobe\Flash Player
%appdata%\Macromedia\Flash Player
(3) Launch Regedit, delete keys from
HKEY_LOCAL_MACHINE\SOFTWARE\Macromedia\FlashPlayer\SafeVersions\
Or, run script I found on a forum (save as a batch file, i.e. script.cmd):
@echo off
echo Commencing Flash cleanup > C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleaning 00AB3E66D3B6B66469AF36907A4FB20B >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Products\00AB3E66D3B6B66469AF36907A4FB20B /f >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Features\00AB3E66D3B6B66469AF36907A4FB20B /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\00AB3E66D3B6B66469AF36907A4FB20BInstaller\Products\ /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Features\00AB3E66D3B6B66469AF36907A4FB20B /f >> C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleaning C460100B160DEAB4091314A638D85563 >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Products\C460100B160DEAB4091314A638D85563 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Features\C460100B160DEAB4091314A638D85563 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\C460100B160DEAB4091314A638D85563 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Features\C460100B160DEAB4091314A638D85563 /f >> C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleaning FE188D887650A344A9485EAAFE92BB43 >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Products\FE188D887650A344A9485EAAFE92BB43 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Features\FE188D887650A344A9485EAAFE92BB43 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\FE188D887650A344A9485EAAFE92BB43 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Features\FE188D887650A344A9485EAAFE92BB43 /f >> C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleaning 5E5CA04FBA55A964ABB838C90E413608 >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Products\5E5CA04FBA55A964ABB838C90E413608 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Features\5E5CA04FBA55A964ABB838C90E413608 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\5E5CA04FBA55A964ABB838C90E413608 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Features\5E5CA04FBA55A964ABB838C90E413608 /f >> C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleaning D90E84CDF5E493049BA3CFDE63FEEB55 >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Products\D90E84CDF5E493049BA3CFDE63FEEB55 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_CLASSES_ROOT\Installer\Features\D90E84CDF5E493049BA3CFDE63FEEB55 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\D90E84CDF5E493049BA3CFDE63FEEB55 /f >> C:\FlashClean.log
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Features\D90E84CDF5E493049BA3CFDE63FEEB55 /f >> C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleaning SafeVersions tree
reg.exe DELETE HKEY_LOCAL_MACHINE\SOFTWARE\Macromedia\FlashPlayer\SafeVersions /f >> C:\FlashClean.log
echo. >> C:\FlashClean.log
echo Cleanup completed >> C:\FlashClean.log
exit 0