8 replies to this topic

[cornel_gav]

I want to disaply a MessageBox informing the user that he's making a downgrade and stop the installation.
How can I do this in InstallShield?

[Stefan Krueger]

It depends on whether you are changing the ProductCode (Major or Minor Upgrade)

[cornel_gav]

Major upgrade.

[Stefan Krueger]

Add a row to the Upgrade table to detect the downgrade, with the "detect only" flag set. Add a type 19 (display error message and exit) custom action to both the UI and the Execute sequence. Use the property from the Upgrade table as condition for the custom action.

[Glytzhkof]

With Installshield 2008 there are now built in Installshield support for this via a default Upgrade table entry and a custom action called ISPreventDowngrade in both sequences.

[Stefan Krueger]

That's true, if you are using InstallShield you don't need to do this manually. However (if I recall correctly) IS 2008 will not add this to projects you migrate from previous InstallShield versions, only for projects you create in IS 2008 from scratch.

[Glytzhkof]

It looks like Installshield will add this custom action whenever the Upgrade table is authored - even for older projects.

[Glytzhkof]

The Upgrade table entry created looks like this:

UpgradeCode: {00000000-0000-0000-0000-000000000000}
VersionMin: ***ALL_VERSIONS***
VersionMax:
Language:
Attributes: 2
Remove:
ActionProperty: ISFOUNDNEWERPRODUCTVERSION
ISDisplayName: ISPreventDowngrade

Anyone know what's up with the GUID and the MinVersion fields. Are these undocumented Microsoft MSI features or some Installshield franken-beast?

[Stefan Krueger]

I believe these are placeholders which get replaced with the actual UpgradeCode and current version number during build. You should only see them in the project file but not in the built msi file.