❗ Important: Email delivery & blocked domains
We attach great importance to working with our interested parties and members to be able to communicate reliably via email. That is why we regularly check whether our messages can be delivered – also to unnecessary support requests to avoid.
Unfortunately, with certain email service providers repeated massive delivery problems – for example through blocked servers, inadequate standards or poor delivery rates.
▶️ For this reason, the following email domains are blocked:
Please do not use these – even if you write to us from there, we cannot not answer.
Apple Inc.:
*@me.com
*@icloud.com
*@mac.com
Deutsche Telekom:
*@t-online.de
*@t-online.com
Mozilla Corporation:
*@*mozmail.com
Hutchison Drei Austria GmbH:
*@drei.at
*@drei.com
La Poste SA:
*@laposte.net
*@laposte.fr
Yahoo! Inc.:
*@aol.com
*@aol.at
*@aol.de
*@yahoo.com
*@yahoo.de
*@yahoo.fi
*@yahoo.fr
*@yahoo.co.uk
*@yahoo.es
*@yahoo.ca
*@yahoo.com.hk
*@yahoo.ie
*@yahoo.at
*@yahoo.com.sg
*@yahoo.it
🛑 Also not allowed are so-called disposable email addresses (“Trashmail” / “Temporary Mail”) – since reliable communication is not possible here.
📧 Email address verification
To protect our communications and to avoid unnecessary errors or support cases, we check every email addressentered via one of our forms (e.g. contact or registration form).
This check is carried out automatically by an external service provider.
▶️ If the address is classified as invalid, unsafe or problematic, it will not be accepted.
✅ Recommendation: Reliable email providers
For smooth communication, we recommend the following email providers, with which we have no delivery problems given:
GMX (e.g. @gmx.at, @gmx.de, @gmx.net)
Google Mail / Gmail (e.g. @gmail.com, @gmail.com)
These providers have proven to be stable and reliable in practice.
(Last updated: March 6, 2026 at 1:28 pm)
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