Automatic folder size calculation

Something has changed resulting in Opus 12 no longer automatically calculating folder sizes; it works fine when I select edit/calculate folder sizes but despite preferences/folders/folder behaviour/calculate folder sizes automatically being checked, Opus 12 does not do this automatically. So, what have I missed, not done etc etc?
As before a screen shot of how to rectify this would be greatly appreciated
Kind regards

Nothing should have changed in Opus 12.

If the general setting is on but not taking effect, you most likely have a folder format overriding the global setting in some or all folders.

It's also possible the size calculation thread has got stuck somehow, in which case fully exiting Opus (via File / Exit Directory Opus) and then opening a new window for a folder on a local drive would cause the calculations to work again, but they would stop working later (including for the same folder).

many thanks, a full turn off seemed to resolve the prob