Email archiving for Microsoft 365 and Google Workspace

What an email archive does

A mailbox is a working tool: people file, edit and delete messages every day. An archive is a record. It captures each message as it passes through your mail system, stores it so nobody can change it, and keeps it searchable until your retention policy says it can go. That is what lets you prove what was said, answer a dispute or a request for information, and keep a former employee's mail without keeping their account.

A compliance-grade email archive brings together six things:

• Journaling capture: the mail system sends a copy of every inbound and outbound message to the archive, so nothing depends on users keeping mail. See email journaling explained.
• Immutable storage: archived messages are held in write-once (WORM) storage, so they cannot be edited or deleted before their retention period ends.
• Retention policies: rules that keep each category of mail for the right length of time and then let it go. See our guide to writing an email retention policy.
• eDiscovery: search across every archived mailbox by sender, recipient, date and keyword, then review, tag and export the results. See email eDiscovery.
• Legal hold: freeze relevant mail when a dispute or investigation is reasonably anticipated, overriding normal deletion. See legal hold.
• Audit trail: a log of who searched, viewed and exported what, so the archive itself can stand up to scrutiny.

If you are new to the subject, start with what is email archiving? and email archiving vs backup.

Why we use NinjaOne Archiver

We focus on one archiving platform rather than reselling many: NinjaOne Archiver, the archiving add-on for NinjaOne SaaS Backup. The product was formerly sold as Dropsuite; NinjaOne completed its acquisition of Dropsuite on 2 June 2025 and now sells it under the NinjaOne name.

It suits small and mid-sized organisations on Microsoft 365 or Google Workspace for a simple reason: the archive and the backup come in the same per-user licence and are managed in the same console. From NinjaOne's own product material and documentation, Archiver gives you:

• Real-time journaling of inbound and outbound mail, with attachments and metadata, captured at server level so messages a user later deletes are still preserved
• Immutable WORM storage with full audit trails, AES-256 encryption, TLS 1.2 in transit, MFA and role-based access, with no on-premises hardware
• Flexible retention from 30 days to over a decade or indefinitely, with policies by user, department or domain
• eDiscovery with saved searches, tagging, alerts when new mail matches a saved search, and search inside attached documents
• Legal hold and review roles: Compliance and Review Officer, Data Protection Officer, Reviewer and Limited Reviewer roles, while the IT Admin role has no access to compliance features
• Backup in the same licence: the Archiver bundles include NinjaOne SaaS Backup Standard for Exchange Online, OneDrive, SharePoint and Teams, or Gmail, Drive, Calendar and Contacts

The four per-user bundles, and exactly what Archiver changes over standard backup, are set out on NinjaOne SaaS Backup Standard vs Archiver bundles. For the backup side on its own, see our Cloud Security site's page on NinjaOne SaaS Backup.

Where to start

Pick the question closest to yours.

Microsoft 365 email archiving

Microsoft 365 has its own archiving and retention features: archive mailboxes, retention policies, eDiscovery and holds in Microsoft Purview. Microsoft recommends using Microsoft 365 retention to manage data in place where possible, and for many organisations that is a sound baseline. Our page on Exchange Online Archiving explains what the archive mailbox does and does not do.

Some organisations still want a separate archive: a copy held outside the tenant, captured by journaling, searchable alongside their backups, and able to keep leavers' mail after their licence is gone. Microsoft documents journaling to an outside archive for exactly that case, and notes that an Exchange Online mailbox cannot itself be the journaling mailbox. NinjaOne Archiver creates the journal rule and distribution group for you after the tenant is authenticated. See Exchange Online journaling and, for chats, Teams chat archiving.

Google Workspace email archiving

In Gmail, the Archive button only takes a message out of the inbox; it stays in the mailbox under All Mail and the user can still delete it. Google Vault adds retention, holds and search, but Google itself says "Vault isn't a data archive", and deleting a user or a required licence can purge their data from Vault.

NinjaOne Archiver archives Gmail in an existing Google Workspace tenant through Gmail routing rules that send a copy of each message to the archive's journal address. Unlike Microsoft 365, this is set up by hand in the Google Admin console, and we can help you set it up. You keep your Google Workspace subscription exactly as it is (we do not sell Google licences); the archive sits alongside it. Read more on Google Workspace email archiving, Google Workspace journaling and Google Vault vs a separate archive.

UK retention rules in brief

No single UK law sets one retention period for all email. The right period depends on what each email is: a contract, an invoice, an HR matter or an everyday conversation. UK GDPR adds a counterweight, because personal data must be kept no longer than necessary. Some sectors have specific rules; FCA-regulated firms in scope of SYSC 10A must keep relevant electronic communications in a durable medium that prevents alteration or deletion.

Our guides set out the sourced reference points: how long to keep emails, email retention and UK GDPR and FCA email retention. They are not legal advice; confirm your periods with your legal or compliance adviser, then we can set the archive's policies to match.

How Forever Systems helps

We supply NinjaOne SaaS Backup with Archiver and help you get it working the way your policy needs. A typical engagement looks like this:

1. Scope: which mailboxes, shared mailboxes and leavers to cover, whether you need Teams private chats, any legacy archive or PST files, and the retention periods you have agreed.
2. Quote: the right bundle and seat count, with the term, the storage allowance tied to paid seats and how leavers count towards seats confirmed at quote, along with where your archive will be held.
3. Set-up: we can help connect your tenant, check journaling is flowing, create retention policies by department or user, and assign compliance and reviewer roles to the right people.
4. Legacy data: where you have an old archive or PST files, we can help plan NinjaOne's ingestion service and prepare the mapping file it needs.
5. Handover: we can show your reviewers how to search, save searches, tag, apply legal hold and export.

Pricing depends on the bundle, the number of users and the term, so ask us for a quote. Contact us with a short description of what you need to keep and why.