What does audit-proof archiving mean?

The four requirements

Completeness. No document is missing.

Unchangeability. Subsequent changes are excluded or fully logged.

Findability. A specific document can be found in a reasonable time – not after two days of searching.

Readability over the period. Eight years for invoices. A format readable today must still be readable then.

Why a network drive is not sufficient

Because anyone with access can replace a file and nothing documents this. The question in the audit is not "was something changed?", but "can you rule out that something was changed?"

What qualifies

• A document management system with write protection and logging
• Storage that keeps files unchangeable for a period
• Archiving functions in the ERP or accounting system

What matters is not the product, but that unchangeability is technically enforced and verifiable.

What belongs there, but is often forgotten

• The structured data part, not just a PDF view
• Attachments of the invoice
• The log, who accessed what when
• A recovery test – an archive from which nothing has ever been retrieved is unverified

During a system change

The old inventory must remain readable for the remaining period. This must be clarified before shutdown, not afterwards.

This text does not replace tax advice.