Thanks for the explanation, Anna.
My main remaining problem is the security image. I copy the text from the security image, yet I receive an error message telling me that the text I entered does not match the security image. After clicking OK, I sometimes see the same security image, which I copy again, with the same result. Sometimes I see a different security image, which I copy, but with the same result once more: the same error message appears.
It usually takes about six to eight attempts before my text is accepted.