Using Installshield 2011, we're creating a major upgrade and having problems upgrading software with this Product Version format - 2009.727.1365. We keep getting the standard 'Installed software is newer than product to be installed' message. With IS 2011, the major version has to be less than 255, from what I can gather, and I think the old format we're using is breaking the check for upgrading.
I've created a test IS project upgrading from 1.00.0000 to 2.00.0000 with no issues, so I'm thinking the issue has to be related to the format of the product version already installed.
Is there a way to use InstallScript or something to compare our old format with the new one and then do an override?
Any help would be greatly appreciated. Thanks in advance!!
You'll probably need to remove or modify the ISPreventDowngrade major-upgrade item, which is what detects and prevents this kind of version downgrade (and which is usually what one wants).
A quick test at this end from version 2010.0.0 to 2.0.0 seems to work with ISPreventDowngrade removed, for example.
