My iPad has suddenly developed a grey rectangular box with each email, both sent and received. the box is approx 6 x 4 cm. I am unable to erase it although when I expand the email the box moves and diminishes in size but re-establishes itself when email is back to normal size. Please help!

One suggestion that I have seen that you could try is to close a few (or even all) applications. Double-click on the Home button, which will show the open apps. Click on the miunus sign to close the app. It won't do any harm to close all of them; you should certainly close the mail app. This has been reported to solve the problem you mention. Let us know if it works for you.
Many thanks! Problem solved and no more grey box, that's great because it was very annoying - big thank you!
