I am trying to use the 4.0d win update installer to upgrade 4.0c, but it says I do not have a valid install of 3.4 or higher. 4.0c is installed on d:\Alfresco. Is there a way to fix this to proceed with the upgrade?
In this issue, the reporter was using a valid/working 3.4 installation and the installer still failed to run reporting the same message that you are seeing.