I've seen folk complain like this and they often won't try gmail for the purchase.
It's not up to Mailchimp to fix a web mail issue at 1and1 is it?
I'm trying to use mailchimp (MC) and they need me to pick up a verification code from my webmail proper and then return and enter it to do a sign up form. But my webmail has nothing in there. But when I ask MC to send to my outlook address it arrives there with a verification code, but which won't work as it's not verifying the MS outlook domain but a 1&1 domain. I'm stuck with no answers to solve this problem. I can't log into their forums, I can't see anywhere else I should post this problem. They're not handling the issue effectively. Might I be doing sth wrong? Isn't there any free alternative that can render even closely to MC that I could start off with first?