internal error - invalid characters

Hi guys. Have you seen something like this below? ... internal error: The string resource has invalid characters in its value internal error: The provided value contains invalid characters: Solarstorm SFN5162F SFP+ Server Adapter this if from journal logs. This hardware model of the NICs which comprise make up a team/bridge which libvirt net use, but what would 'libvirtd' bother with that? many thanks, L.