How to update Windows installer package over installed msi with same product id

Question

I have created a wix installer project which is working fine. It installs my application on system easily. whenever if there is any change in any file or service, i uninstall msi from controk panel and installs new msi on system.

But whenever i install new msi, application's all setting change after new installation, that doesn't sound good. For sort out this, i am using Upgrade code in Product.wxs file. But when i install new msi after build, but is shows given error:

Another version of this product is already installed.  Installation of this version cannot continue.  To configure or remove the existing version of this product, use Add/Remove Programs on the Control Panel

So, i want to update windows application package whenever there is any change in files and with same Product id. I just want to update installed msi, dont want to remove that.

Answer 1

You cannot use the same ProductId to do upgrades, you need to change it. The best way is to set ProductId="*" and this will change it for every build. You will also need to increase the version number and this best done by using the main exe assembly version number. See http://wix.sourceforge.net/manual-wix3/major_upgrade.htm for more info.

Answer 2

You can use the same ProductCode to update an installed MSI. Basically you increment the ProductVersion, rebuild the MSI (with new PackageCode) and do a minor update with a command line such as:

msiexec /i <path to new msi> REINSTALL=ALL REINSTALLMODE=vomus. 

In my experience this not commonly used because if you're going to rebuild the MSI you may as well upgrade with a major upgrade.

If all you want are updates to a few files and you're not ready to ship a complete MSI file, then that's what patches are for. Rebuild the MSI as above, then build a patch - the patch is the delta between the two MSI files, see docs for MsiMsp.exe.