I cannot install Reader 9.0, 9.30 or 9.33, downloaded from the Adobe site with Firefox, and installing on Windows XP.
I get an error message saying " the file ......Acroread 9.0.msi is not a valid installation package for the product Reader 7.0.5. "
Every file comes up with a similar message, looking for the Version 7.0.5 msi file.
What on earth is going on? How do I install? I need a full installation, not just an upgrade, because I deleted version 8, thinking that it would interfere with version 9. (silly move, in hindsight!)
run the microsoft installer cleanup tool to remove all vestiges of previous versions in your registry.
The Windows Installer Cleanup Utility mentioned by Michael is not longer supplied by Microsoft, but it can still be obtained by various 3rd-part download sites such as http://majorgeeks.com/Windows_Installer_CleanUp_Utility_d4459.html