How do I make a WIX MSI always remove a previous version?

Question

I have CI build system builds an MSI whenever a developer checks in a change. We run automated acceptance tests on the installed MSI.

Basically every MSI is a comple

Answer 1

So I did find a way of doing it without changing the version number.

I change the Product GUID with every build, but keep the Upgrade GUID the same.

I also had to change the RemoveExistingProducts to Before='InstallInitialize'. Otherwise it left only the 'deltas' between builds in the install path.

As noted by Wim below, I can replace the generated Product GUID with '*'.