Repeated error messages - are they important or not??

[stoat]

I am a newbie running a basic Freenas as a backup server and also Plex. It's been working fine, with the exception of one corrupted flash drive early on which I replaced and since then no issues.
However, I keep receiving (almost daily) alerts and am unsure whether I need to do anything about them! They sound like they are informational - but I'm not sure and can't find a reference to decode what the error messages actually mean. If someone could advise, that would be really appreciated. Thank you in advance

The messages are: Unable to run alert source 'ZpoolCapacity' and Unable to run alert source 'Samba4'

 

[dlavigne]

Which FreeNAS version?

 

[stoat]

Thanks - 11.2RC2

 

[dlavigne]

Do the messages persist if you update to 11.2-U6?