Thanks everyone for your help. I haven't yet migrated to Greenby - have they forgotten me?
Unfortunately I haven't been able to get back to the error message re the certificate to look at the details page.
I also tried using her email address as her username, but it didn't work.
However, I have added my wife's account onto my iPad 7 using the same settings and it works, SSL and all.
So it looks like a trip to John Lewis to buy her a new iPad.
Thanks once again,
Dave
