Thank you in advance for considering this question. If a similar question existed, I was unable to find it.
The Issue: Our company packages an application into an MSI. This MSI when installed outside of any GPO properly updates, blocks attempts to downgrade (or move from a higher revision to a lower revision), and never has trouble uninstalling previous versions of the application regardless of how long ago those versions were created/installed. For example, we can install version 1.2.3 and then install version 2.3.4 and the application will properly install without issue. However, we work with a customer who uses GPO to deploy our application to hundreds of PC's. Each time we have provided an updated version of the application the following has been indicated:
On any machine where a previous version of our application was installed via GPO, no matter what the previous version is, the update successfully installs without issue.
On a machine where the application was manually installed (outside of the GPO), and an attempt to update the application via GPO is made - either the application is installed in addition to the old version, OR there remain registry keys to the previous version of the application and the application cannot open/run correctly. In this case the registry keys must be manually removed, and the install is then attempted again from a clean machine.
What we know is that on any machine where the application was originally installed via GPO - updating the application is no problem. On every machine where the application was not installed with the GPO in the first place, updating via GPO fails with one of the problems presented above.
My question is: Is there a technical issue with how the installation is being handled partially through the GPO and partially outside? Does the GPO need to be responsible for the entire life-cycle of the application? OR is it a reasonable expectation that the application be updated both on machines where the original version was manually (outside the GPO ) installed, and when it was installed initially from within the GPO?
One solution we are aware of is simply having all computers manage the application life-cycle (since we know updates work in that environment already), however this would mean that many computers would need to have the manually installed versions removed by hand - and then properly handle the installation through GPO which is an extensive bit of work.
We would greatly welcome any solutions, references to technical documentation that formally shed light on the proper management or expectations here, or links to information. Our research suggests that it is "best" to manage the entire applications life-cycle inside the GPO - but I have as of yet been unable to determine that it is 100% necessary to do so.
Looking forward to any assistance. If any further technical details are required to help the viability of the question, please don't hesitate to request such details.
If you end up with two versions installed in Control Panel, then all other things being correct, the most likely explanation is that you upgraded a per user install with a per machine install (or vice versa). In the GPO world that's related to assigning it to a user or to the computer, something like that. That's easy to verify by getting a verbose log and checking the FindRelatedProducts actions for an indication that another product was found but in a different context.
When you're in GPO mode all the time, I assume each one (whether it's per user or per machine) is consistent, therefore upgrades always work, but they don't work cross-context.
I believe GPO suppresses the UI in most cases, and the UI (or the UI sequence) is sometimes where per user/per machine is set. That might be something else that would cause it, depending on how the GPO publishes to the computer or the user.