Hi,
it was a result of an automatic update to WP 4.3.3.
The Mountain Creek Theme that is still working is 1.1.0.
The one that gave the problem must have been one of the updates after that.
Hi,
I have solved the problem by replacing the ‘Mountain Creek’ and ‘Mountain Creek Child’ directories on the server by a backup.
A screenshot is of the faulty lay out is here.
Regards,
Dirk