How to restore the system during major upgrade failures
Hi,
Major Upgrade Worries:
Major upgrade is first uninstall existing version and then install the latest version. But after uninstallation of existing version, if an error occur during installation of new version, the system will be in an undefined state.
Is there any support in InstallShield 2019 R3 to revert the system to the state prior to major upgrade if the upgrade fails ?
This is a common question when using windows installer technology and performing a Major Upgrade. One thing to be aware of here is that it is Microsoft's Windows Installer which is controlling the Major Upgrade and it is Microsoft's upgrade rules that we have to follow when we create one.
It would be possible to move the "RemoveExistingProducts" action to after the "InstallFinalize" action. This would mean that all the files are installed first and then all the unneeded files are removed.
You can apply this change in Installshield in the Upgrades View. Select "Upgrade Windows Installer Setup" and then select the bullet point for "Install Setup then remove unneeded files"
This is not a true Major Upgrade and care must be taken to fully test that the installation works as expected with this option selected.
