A zip file of the new version 15.0 CD was just posted to Download Center earlier today. (The new version does not show up in the navigation/search results because it is too new to be in the index.) The new version might succeed in upgrading over your current installation. If the upgrade works, I recommend uninstalling the software and doing a clean install just to make sure all the right files are in place and the old ones are gone.
If the upgrade to version 15.0 does not work, you should try the procedures at Unable to uninstall network adapter drivers and/or teams.
I hope this helps you.
Version 5 gives me the same "not supported for upgrades" message. I tried the manual uninstall that you referenced, but that only made matters worse and I couldn't get back to where I started. I've physically removed the PRO/1000 PT for the time being and I'm back up and running on the server's on-board broadcom nic.
I can't upgrade to Proset version 15.1.1 because it can't uninstall older version 14.3 . . When I try to uninstall through Control Panel\Programs and Features, I get "Product: Intel(R) Network Connections -- The installed version of Intel PROSet is not supported for upgrades. You must uninstall it before installing this version Upgrade to version 15.1.1
Manual uninstall does not apply to Windows 7.
The stage is an update from Windows Vista with PROSet 14.3 installed to Windows 7.
Thank You very much