I've searched for this topic and found many posts but none that describe the exact issue I'm having. Our product (which I inherited from another developer) had an InstallScript method (see below) that although it seemed to work for quite a while didn't seem to be called from anywhere, so I added a custom action to call it and put it after the ISSetupFilesExtract step in both the User Interface and Execute Sequences and when I run it it either doesn't work or gives me an error. So here's the script:
export prototype MainApplication_Installing();
function MainApplication_Installing()
begin
Disable(CANCELBUTTON);
SetStatusWindow(-1,"Uninstalling previous versions...");
//Uninstall 3.0.5
LaunchApp("MsiExec.exe","/X{ABA98465-AE8B-49BB-A445-46744EF236C0} /qn");
//Uninstall 3.1.1
LaunchApp("MsiExec.exe","/X{954ADD40-DFEF-40DD-896A-FF29E5E43FB8} /qn");
where the /X is the product code of each prior version, but like I said this didn't work, so after a failed attempt to debug the script I tried a different route creating a Major Upgrade where I specified the Upgrade code of each prior version under: Prepare Setup for Upgrade Scenarios->Upgrade Windows Installer Setup->Remove 3.05 - 3.1.1, but that's not working either. When I install the product now it installs it parallel to the older version (I see both in Control-Panel->Uninstall or Change Program.
So which way should I do it and why aren't either of these working?
Thanks in advance!
Once your install/uninstall is in the InstallExecuteSequence you can not run another install/uninstall process. This is a limitation with Windows installer that only one MSI process can be running at a time.