You may notice that you have older application metering agents in your environment. You do have the upgrade policies enabled, and you have verified the upgrade has been run on these endpoints. Still, the older agent is showing as installed.
Application Metering 8.x
The endpoint most likely had a much older version of the Application Metering agent installed. At that time, the agent installation used a different MSI product code. When the new install runs, it tries to uninstall the old version and cannot.
You may have tried to copy the AMAgentSetup_x64.msi from the SMP server, located by default at: C:\Program Files\Altiris\Notification Server\NSCap\bin\Win64\X64\Inventory\Application Metering\Agent Package. When running this MSI on the endpoint, to uninstall it, you may notice that you receive the following error:
What you want to do is search the registry, both the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
and the HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall
keys for anything related to Application Metering. Once you find it, look for the uninstall string and copy that from the registry. It will start with MSIEXEC /I, which is wrong. Change it to MSIEXEC /x and run it with the GUID shown in an administrative command prompt. For an example:
As another option, you can try using a third-party utility called UninstallView. The utility can be downloaded from the vendor's website here: UnintallView