Gemma, thank you for that suggestion.
What I am seeing looks a little different, so it might be that I am looking in the wrong place.
But, I checked the version again, and we are not on the latest version.
I'll try updating and see if that is what was needed.
EDIT: Solved, issue was old version of addon, updating resolved my problem
We are having some trouble with the Private Thread addon and the latest version of XenForo : 2.2.12
The option within the more options menu, that should allow us to mark a thread as private, is no longer avaiable.
We...