Thanks Nigel. I used the address [email protected] (which does exist) and everything works fine.
I still have my PGV site and I tried creating a bogus user. The messages did have the ‘From’ address as [email protected] (which does not exist). So what I didn’t understand is why the non-existent address works for PGV but not for kiwitrees. However, It’s not worth pursuing this, since you did resolve the problem for kiwitrees.