In Germany, the property tax had to be reformed due to a ruling by the Federal Constitutional Court. So this year everybody got a mail with the request to register his property from july 1st up to the end of the year.
This should be done via ELSTER = electronic tax declaration (explanation of the acronym can be found here)
I tried this yesterday and today, but the login page does not respond at all.
Today a message was posted on their website (orange box on the screenshot)
Restrictions when using the ElsterSmart app
It is currently not possible to use Mein ELSTER using the ElsterSmart app if the ElsterSmart app and Mein ELSTER are used on different devices (e.g. if you have installed ElsterSmart on your smartphone or tablet, but Mein ELSTER in the browser on your use PC).
and
Availability Limitations
Due to the enormous interest in the forms for the property tax reform, there are currently restrictions on availability. We are already working intensively on being able to provide you with the usual quality as quickly as possible.
I think just at least 10 million citizens try to follow the request and the on datacenter the servers are on their limit:
Even the status page shows a 404: https://www.elster.de/elsterweb/svs
So let's see if it is possible to follow the request until end of the year or if this deadline gets extended for some years :).
