1

I have an Installshield Basic MSI Project with prerequisites. Once the user tries to run the setup.exe file, it shows the prerequisites dialog and the user is able to install the prerequisites successfully as expected.

After the application is installed successfully, the user removes one of the prerequisites.

Later the user tries to modify the installation by double clicking the setup.exe. The installation shows the prerequisites dialog as expected before proceeding with the modification.

But if the user tries to modify the installation from Add/Remove programs (using the change option) the installation does not shows the prerequisites dialog.

My questions are as below: 1. Why prerequisites dialog is shown only when user clicks the setup.exe and not from Add/Remove programs 2. What is the expected behaviour when the user tries to modify from Add/Remove programs and one of the prerequisites is missing.

Surender Panuganti
  • 333
  • 1
  • 5
  • 14
  • I would add a check runtime environment on launch for my application and then verify that all prerequisites are in place. If they are not I would tell the user to run the original setup.exe again. – Stein Åsmul Jun 13 '14 at 14:44

2 Answers2

1

I don't know of any setup tool that revisits prerequisites in maintenance mode. The assumption is that you install all the prerequisites for the product at the start, and if the user doesn't know why they are there that doesn't mean uninstall them. So the expected behavior is that you add and remove features. Keep in mind that a separate setup.exe typically installs the prerequisites, not the MSI.

The issues include these:

Many prerequisites require admin privilege to install, and if the current user of the app is a limited user then the user will not be able to install them anyway.

If the prerequisite was downloaded from the network and the user is now disconnected then it won't download for install.

It's not obvious that the feature you may be about to add actually requires the missing prerequisite. I know of many products where a prerequisite is used only by a small part of the product, so adding a feature doesn't necessarily require one of the prerequisites, so unless a vendor lets you define a map saying "these features require these prerequisites" then running prerequisite checks again is a waste of time.

PhilDW
  • 20,260
  • 1
  • 18
  • 28
  • My product installation is dependent on the missing prerequisite (a DB server) and it is a setup prerequisite and not a feature prerequisite. Now since in maintenance mode the setup tool does not revisits prerequisites, is it fine to have a custom action to check if the prerequisite is available when the user enters maintenance mode and abort the setup if the prerequisite is missing. Thanks in advance. – Surender Panuganti Jun 12 '14 at 19:36
0

The behaviour is different when running the installer from the Add/Remove Programs Panel, because you are not running the whole Installer.

Actually, when you build a MSI installer with InstallShield, you get a "Disk 1" Folder, containing :

  • YourProduct.msi
  • a setup.exe file
  • folder containing your prerequisites, named ISSetupPrerequisites

(Or else you can get a single setup.exe file, that includes all of these items...)

If I understood it right, the prerequisites are not checked by the msi itself, but by the setup.exe.

When you run the MSI through the Add/Remove Programs panel, Windows looks for the msi, that has automatically been stored in %WinDir%\Installer. The problem is that only the msi is stored there, but the setup.exe and the prerequisites aren't, so the prerequisites cannot be checked nor installed this way.

If you want to check some condition at the beginning of your installer in order to interrupt the installation if your prerequisites are not met, then you should look at the "LaunchCondition" action.

http://helpnet.installshield.com/installshield16helplib/IHelpProdCondition.htm

Gruntzy
  • 423
  • 2
  • 7