Basic tone settings causing export error

I can always try it again but this has actually happened on two separate catalogues.

Yes I saw that one, thanks, but resetting the preferences doesn't seem to change the problem.

The only workaround I have now is to make a mask which covers the whole area and then apply these basic tone settings to that. The problem is it's a panoramic image and the edges of the mask tend to not have the perfect applied equally so you get a kind of line through your panorama.

In your first post you mention an error message when exporting JPEG image. However, your screenshot indicates that the image is a Tiff file.  Can you clarify whether it's both file types or that JPEG was an error in your first post.