First of all, I think it's important people understand what the word "GMX" means. GMX is a company that offers mail services, just like Google with Gmail or Microsoft with Outlook. Now you may ask, why use GMX.com mails? Well, they are the best overall to use as a email provider because of the following reasons;
1. The emails never gets clipped - GMX doesn't really care about botted or mass created GMX mails.
2. Every GMX.com email account has IMAP access which means bots could connect to your mails without having to forward your mails. Learn about GMX IMAP Access.
3. GMX is a worldwide known company which doesn't open the suspecting eye of Nike.
4. You can forward your GMX mails to multiple emails without a hassle, compared to companies like gmail which makes forwarding setup a very hard process.
Now that you know how powerful GMX mails are, let us tell you how to forward all of your GMX mails to one master mail.