I have a work around until someone tells me how to actually fix this.
It seems the uninstaller didn't do its job very well. I found the following folder present on my server (looking at the path of the file it says its looking for):
C:\InetPub\SolarWinds\orion\NCM
I stopped IIS and renamed it to: C:\InetPub\SolarWinds\orion\_NCM
And now it works.
Can I just delete this folder? I wonder what else the uninstaller left behind...