Signed e-mails from e-rechnung@gkm-buchhaltung.de

Companies can send their e-invoices via GKM Buchhaltung from the address e-rechnung@gkm-buchhaltung.de. The issuer of the invoice is always the company named in the e-mail. Please direct questions about the invoice to that company; messages to e-rechnung@gkm-buchhaltung.de are not read.

The signature

The signature is being set up. Until then the e-mails are sent without a signature. The company named can confirm whether an e-mail is genuine.

How to verify the signature

  • Outlook and Apple Mail show a seal or tick next to the sender if the signature is valid. Clicking it shows the certificate.
  • Check that the certificate is issued to e-rechnung@gkm-buchhaltung.de and GKM Global GmbH and that the fingerprint matches the one below.
  • Some browser-based programs do not verify S/MIME signatures and show a file smime.p7s as an attachment instead. This does not damage the e-mail.
  • If your program reports an invalid signature, the message was altered after sending or your program is missing the certificate of the issuing authority.