I have the same problem too.
I tried to install Acrobat Standard 6 on my new computer. But Windows said there were known issues and I couldn’t install it. So I downloaded the upgrade Ac60BaP1.exe file. But when I tried to install it, I got this message:
"The upgrade patch cannot be installed by the Windows Installer service because the program to be upgraded may be missing, or the upgrade patch may upgrade a different version of the program. Verify that the program to be upgraded exists on your computer and that you have the correct upgrade patch."
The help chat line couldn't help me as the product is too old! And I'm not brave enough to go in and change registry stuff!
Speedie