I am looking for a replacement for InstallShield. Unfortunately we only have 1 license for InstallShield and it was installed on a developer’s machine. I’m considering switching over to WiX, but after reading the documentation there is a Product ID GUID, Upgrade Code GUID and a Package GUID.
I also know GUID’s were created by InstallShield. If I switch over to WiX can I start using new GUID’s or do I have use some of the GUID’s created by InstallShield? If an upgrade to a product is released will switching installers hose customers who had the old installer?
In order to be able to upgrade your old package, you need to use (and find out) your old upgrade code.
The Package code should be different (ie autogenerated) for every different MSI (the MSI can be cached with the guid as cache key).
The Product code should be different between major upgrade, but is important for minor upgrades and patches. I haven’t used wix to do anything else than major upgrades right now, so I don’t know the exact details
See the MSDN article on patching and upgrades as well as the WiX Tutorial