senn-techEmail Archiving: GoBD-Compliant, On-Premises, No Lock-in
Whoever deletes business emails — or keeps them lying around in inboxes indefinitely — isn't risking an IT problem, but a tax one. Emails count as commercial records, and the moment one contains an invoice, a contract, or a booking reference, retention law applies.
What's actually required
- Duration: Six years (commercial) or ten years when a booking reference derives from it — counted from year-end.
- Immutability: Archive and original must remain identical. Every access must be logged (WORM — Write Once, Read Many).
- Searchability: A full-text search that an auditor can actually operate in the case that matters. Inboxes are not archives.
- Completeness: Everything that enters the system is captured — automatically, not by feel.
Why on-premises
SaaS archiving shifts the compliance risk into a data center whose location and sub-processors you don't control. For sensitive client and billing correspondence that's not a theoretical objection: whoever archives remains the data controller under privacy law — and must be able to prove where the data sits.
With Open Archiver on our own hardware, IMAP pull, full-text indexing (Meilisearch), content analysis (Apache Tika), and Postgres storage all run inside our own network. The mail never leaves the building.
How the pull works
- The archiver connects via IMAP to every mailbox to be archived — internal or externally hosted alike.
- New messages are pulled, indexed, and stored immutably.
- Mailboxes stay untouched — staff can still delete and tidy up; the archive remains complete.
Our Take
Capping mailbox sizes is treating the symptom. The real problem is missing auditability. Anyone who has once faced a tax or legal request requiring six years of email history never archives optionally again. The operating cost of Open Archiver on-prem is low — the failure cost of missing archiving is not.
How long do business emails actually need to be retained?+
Six years commercially, ten years when a booking reference derives from them — counted from year-end. The moment an email contains an invoice, a contract, or a booking reference, retention law applies. Inboxes are not archives: tidying or deleting breaches the duty. That is why everything entering the system is captured automatically and immutably.
Isn’t cloud archiving enough for the GoBD obligation?+
Technically often yes, but it shifts the compliance risk into a data center whose location and sub-processors you don’t control. Whoever archives remains the data controller under privacy law and must be able to prove where the data sits. With Open Archiver on-prem, IMAP pull, full-text indexing, and storage all run inside your own network — the mail never leaves the building.
What does audit-proof actually mean in practice?+
Immutability (WORM), completeness, and searchability. Every access to the archive must be loggable, a full-text search must be operable by an auditor, and nothing may be lost. The archiver pulls new messages via IMAP and stores them immutably — staff can still delete in their inbox, the archive remains complete.