G'day there J McGimpsey & Peter T,

Do you have a Conditional Format applied?

Yes!!! That was it!!

There wasn't supposed to be a Conditional Format set, but I think
I deleted and added a row or two above my list ages ago and it's
possibly readjusted itself without my noticing. I'm not sure.

As it turned out, one of the conditional formats (simply rows of
alternating background colours) exactly matches the format for my header
row so I never noticed that it was conditional, not hard wired.

Thanks very much for your assistance. I doubt I'd have found it
without being pointed directly at it (even though I cursed & swore for
hours, I still couldn't see it. Maybe I should try a different problem
solving technique?)

Thanks again.

--
See ya,
Ken McLennan
Qld, Australia