Different builds of the same package are considered as different packages

[pepone]

I'm using "WixToolset.Sdk/6.0.0" to build my MSI installer. However, each time I rebuild the MSI, it produces what appears to be a different product. For example, I can install the new MSI even if the previous version (from the last build) is already installed.

I expected that running the new installer would detect the existing installation and display the "Change, Repair, or Remove" dialog. Instead, it shows the standard installation dialog, and I end up with what looks like two identical products installed side by side.

Is this expected behavior? Should I configure something to ensure that rebuilds produce MSIs that are recognized as the same product?

[wmanning]

I think the product ID has to remain the same for it to be considered the same product. The ID attribute here: https://docs.firegiant.com/wix3/xsd/wix/product/.

By default if it is not specified or set to "*" it will generate a new ID each build.

[wmanning]

So you are using v4 and not v6? The Id attribute under Product is only supported in Wix v6. I imagine Wix v4 is ignoring that attribute but not sure. I see you do set the ProductCode (edit: I meant UpgradeCode) so should be good.

Are you changing the first three fields of the version between builds? MSI ignores the forth field. I believe in the case of only a difference in the fourth field (or all four fields the same) it allows side by side installation no matter the upgrade code.

[pepone]

Sorry for the confusion I use wixtolset v6, What I mean is the v4 schema (still used in v6 if I'm not confused) doesn't have product element just package https://docs.firegiant.com/wix/schema/wxs/package/

https://docs.firegiant.com/wix/whatsnew/#guids-are-now-optional-for-upgrade-codes

By reading the above I thought that setting the Id should be enough, and to different build should be just considered the same package but something doesn't seem to work.

[wmanning]

Yes Id is enough. You do not need the "UpgradeCode" since you are using the Id attribute. I don't know what happens when both are specified (maybe the UpgradeCode overrides the Id?).

[pepone]

When I only set the Id, two separate builds are consider different products and you can end up with two identical installs

This doesn't seem to match the documented behavior.

[wmanning]

That's standard behaviour if the versions are the same. Not sure if it's documented. It does surprise people.

If the ProductCode is not set, on each build wix will generate a new productCode (GUID) for the MSI and thus it is considered a different product. If the two versions are the same they are installed side by side (no major upgrade). If the versions are different then it works as expected (a major upgrade from one version to the other).

MSI only looks at the first three fields of the version number. If they match the versions are considered the same.

[robmen]

Is this expected behavior?

It is expected behavior in the Windows Installer, even if it isn't really intuitive. Every build creates a unique package. You need to change one of the first parts of the version to do a major upgrade.

Should I configure something to ensure that rebuilds produce MSIs that are recognized as the same product?

You can do "same version upgrades" but there are some less desirable behaviors with that so it isn't the default. Honestly, it's better to just know that every build creates a unique package and if you don't change the version number that you get this behavior. It's just a less desirable dev behavior because you shouldn't ship the same version out to customers. That just leads to madness. :)