Upgrade Code same but old version not uninstalled
Usually when we release a new version, we change the ProductCode and leave the UpgradeCode intact. This way, when a user installs a new version MSI, the old version is automatically removed.
However, currently we're experiencing a problem where a version 18.104.22.168 is installed on a user's box and when he installs, 1.1.39.00, the old version is not removed. As a result, both versions are listed in Add/Remove Programs as separate installed applications.
We used Microsoft's ORCA applcation to look inside both MSI and confirmed that the product codes are different and the upgrade codes are the same.
What could be the cause of this behavior?
Have you verified the VersionMin and VersionMax values of the Upgrade Table?
I would also look at what you have in the Attributes column.
The Default Express setting for the Attributes column is