I can confirm that with the standard German keyboard and setuo, the mail user interface closes the moment you press the "Alt Gr" key. So, you cannot enter the character "@" from the German keyboard, as you would need to press "Alt Gr + q" for "@".
It is not related. One of their network hardware piece went belly-up, i.e. hardware failure. Expect a lot of network people sitting in a room now, trying to restore routing tables, so that the servers can be reached again from the outside world. No ETA yet. But I guess the good news is that nobody will complain if the…