Email archiving for Microsoft 365, tamper-proof and searchable
Archive every email in write-once storage, prove its integrity with hash chains and find it again in seconds — for audits, legal disputes and the retention periods your business has to keep.
A mailbox is not an archive
Businesses have to keep commercial and tax-relevant emails for years — complete, unaltered and retrievable. A mailbox can be edited, emptied and deleted by its users and admins, and Outlook folders or an export to OneDrive are not tamper-proof storage.
An archive has to show that nothing was changed since an email was stored, keep every message for the full retention period and let you hand over exactly the emails an auditor or a court asks for.
What makes the archive trustworthy
Write once, verify at any time, find in seconds.
Write-once storage (WORM)
Once sealed, archive data is protected against modification and deletion by database-level triggers — including against actions by application administrators.
Integrity you can prove
Every archived item is part of a SHA-256 hash chain, and integrity is verified automatically on a schedule. Any change would break the chain.
Retention from 1 to 10 years
Configure retention per workload, from one year up to ten, with automatic enforcement. Legal hold keeps items beyond that until you release them.
eDiscovery and export
Search bodies and attachments across all mailboxes, collect the results in eDiscovery cases and export them in standard formats for auditors and legal teams.
How it works
- 01
Connect Exchange Online
Connect your Microsoft 365 tenant: existing email is archived first, new email follows automatically.
- 02
Set retention and sealing
Choose how long emails are kept. Archived data is sealed and from then on protected against modification and deletion.
- 03
Search, hold and export
Find emails by content, sender or date, place them on legal hold and export them when needed.
Frequently asked questions
- What is the difference between a backup and an archive?
- A backup brings lost data back quickly. An archive keeps data unaltered for a fixed period and proves that it was not changed. GraphCapsule combines both in one platform: emails can be restored to Microsoft 365 at any time, and the archive is sealed so it stays tamper-proof.
- Isn't the Exchange Online archive mailbox enough?
- The online archive mailbox is extra storage inside Exchange, not a tamper-proof archive: its content can be moved and deleted like any other email unless a retention policy prevents it, and it lives in the same tenant. An independent WORM archive keeps an unalterable copy outside Microsoft 365.
- How long can emails be kept?
- From one to ten years, depending on your plan and your retention policy. Items on legal hold are kept until the hold is released.
- Can I prove that an email was not changed?
- Yes. Every archived item is part of a SHA-256 hash chain, and integrity checks run automatically. A modified item would no longer match its hash.
- Which plans include WORM archiving?
- WORM archiving, legal hold and eDiscovery exports are included in the Professional and Enterprise plans. The pricing page has the full comparison.
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