As the dialog says, uninstall the agents from Add/Remove Programs.
Then, open registry editor (regedit) and navigate to the following keys. If they exist, try the following (Thanks to Kumar!):
HKEY_CLASSES_ROOT\Installer\UpgradeCodes\5EFC92935729A9549B6359B25729535D
HKEY_CLASSES_ROOT\Installer\UpgradeCodes\BBB3CCA2C3EAA714893A84DD07E26E74
If this does not help, check the below
Since, install from portal is trigger based on Active-X, could you check if the Active-X is the right version there. Here is how you can check this
Open Internet Explorer > navigate to "Tools" menu > Internet Options' General Tab > Settings (under browser history if IE 7 or later) > View Objects. Look for "LaunchObj Class". If found check the version from the "Versions" tab. If it matches 6,2,0,924 then the Active-X object is installed but not the agent. If the object is there but a different version then upgrade should be triggered.
If you still have problem, can you give some additional info? Is this a VM? If so, is it possible you had a previous install left in an unstable state? Also, please send the install log called AppStreamClient.log typically at C:\
Hope this helps.