Contact Information for

owner: Dipl.-Ing. Elmar Stellnberger
Ringmauergasse 2
9500 Villach

Jabber:   ( is being phased out)
SIP/[TEL]:     [00] 43 720 513 688
landline phone: 0043 463 266390 (during week)

donation information

account owner: Elmar Stellnberger
IBAN: DE23100110012621227393
Paypal: try to use this in case you can not make a bank transfer


Register at a free XMPP/Jabber service like or ask us for an Jabber address. Use a client like Pidgin, Empathy or Gajim. For MacOS there is Adium. Gajim has a good anti-spam plugin as it was useful in the late days of Jabber/ (normally not required); for manual cert verification with a̅tea use Gajim v1.2.0. Note that with Pidgin contacts are always displayed as offline until you obtain authorization by the respective contact address.
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Encryption would in deed only make real sense if both sides had uncompromised hardware with no backdoors, which is likely not the case. I am not aware of any such hardware.

online-GnuPG/PGP-key: estellnb.revoke.asc   (please follow the guidelines below.)
online-GnuPG/PGP-key fingerprint: 41B8007354A9AE206BC1 011EA8FD357202530C63
offline-GnuPG/PGP-key: estellnb-offline.pubkey.asc   (please follow the guidelines below.)
offline-GnuPG/PGP-key fingerprint: A6975E6D3E8EFA7DF8E9   BD4CEEA646266F18B461
The private key for, ID F515A0D2 has been lost, as has the revocation certificate, which is why we were no longer able to delete the key from public servers. The key 8F026D4725B056DA66BD  BA960B81C3D53245A7F4 is compromized and also must not be used any more.

It is up to you whether you wanna use our secure key for online encryption (3072bit) or our offline-key with 4096bit. You need to comply with the same security precautions as we do when using these keys! In the meantime both keys have been secured via gpg-smartcard. You may need to wait somewhat longer when you send us an encrypted message (possibly longer for the offline key).

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Instructions on how to use the GPG key

These guidelines are all good, correct and valuable and should then also be followed when encrypting.

Please make sure that you

  1. Obtain a genuine copy of our public gpg key.
  2. Do not encrypt or store private keys on a computer which is online but not protected sufficiently (for details please read our article about GnuPG!).
  3. Always keep your private key with you (f.i. on an USB stick) / Never leave it unattended.
  4. Try to avoid using a computer which could have been compromised even if that computer is offline.
  5. Include your own public key for a response.
  6. To stay anonymous you may use a throwaway e-mail via Tor.
  7. Tell us that you have complied with these instructions.
  8. The most sensitive information may require a secure destruction of the private key after the message has been read.

If you should have sent us an encrypted message we will send you another message with the content 'ACK' back timely. It will indicate that we have received the message in deed. However we will likely not have read your message until then yet!

More detailed instructions on what to do can be fetched via software/GnuPG-usage.html.en.

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