can't install windows defender beta 2

[Guest]

i downloaded windows defender beta 2 fine, but when i try to install, it says
"The windows installer service could not be accessed. This can occur if you
are running in safe mode , or if the windows installer is not correctly
installed. Contact your support personnel for assistance." I am not in safe
mode and have the newest version of windows installer, can anyone help?
Thanks.

 

[Guest]

http://msdn.microsoft.com/library/d...us/msi/setup/windows_installer_start_page.asp