MailStore Server Alternatives: Pick by Who the Archive Is For

This page is for anyone looking for a MailStore Server alternative. MailStore Server is the paid edition for companies: one central archive for many mailboxes, with retention rules, legal hold and audit logs. If that is what you need, the honest answer is another server product, such as Piler, Mail-Archiver or Open Archiver, or the retention tools already built into Microsoft 365 and Google Workspace. MailVault is not one of them. It is a desktop app for one person's own mail. If you are comparing the free home edition instead, read MailVault vs MailStore Home. For every option side by side, see MailStore alternatives compared.

What MailStore Server does

MailStore describes Server as email archiving software for small and medium-sized businesses. This is what its product page lists today:

• Platform: Windows 11 and Windows Server 2016 to 2025.
• Price: from 295 EUR plus VAT for a starter kit of five users, with one year of Standard Update & Support. The minimum order is five users, and one installation supports up to 2,000 users. There is a 30-day trial.
• Sources: Microsoft 365, Exchange Server, Google Workspace, any IMAP or POP3 server, PST and EML files, and journaling, so mail can be archived before it reaches a mailbox.
• Compliance: retention policies, legal hold, an audit log, and an Auditor user type for outside auditors. It stores SHA hash values of the content and encrypts the archive with AES-256.
• Access: staff search the archive from an Outlook add-in or a web interface that works on phones.

MailStore is a subsidiary of OpenText. Those features are why companies buy it, and any real replacement needs most of them.

MailStore Server alternatives for an organisation

Last checked: October 2026. Features and prices change, so confirm them on each vendor's site.

Piler

Piler is the closest open-source match for the compliance side of MailStore Server. Its Open Source Edition is free. It takes mail over SMTP, ingests Office 365 and Google accounts, reads EML, Maildir and mailbox files, and includes archival and retention rules, legal hold, audit logs, deduplication and message encryption. The Enterprise Edition is paid, with published pricing tiers, and adds eDiscovery, multi-tenancy and optional paid support.

Mail-Archiver

Mail-Archiver (not the Mac app Mail Archiver X) suits a small office that wants one web page where several people search archived mail. It syncs IMAP accounts and Microsoft 365 through Microsoft Graph, imports MBOX and zipped EML files, and exports to the same formats. Users get per-account permissions, and it can sign people in with OpenID Connect. It can delete mail from the server after a period you set per account, and one setting blocks manual deletion from the archive. It does not serve HTTPS itself, so it needs a reverse proxy in front.

Open Archiver

Open Archiver ingests Google Workspace, Microsoft 365, IMAP, and PST, MBOX and EML files. It indexes message text and attachments such as PDF and DOCX, stores a hash of each email at ingestion so changes can be detected, and keeps an audit trail. Its README still lists legal hold as to be done, so check the current state before you rely on it for a dispute.

The tools your provider already has

If your company already pays for Microsoft 365 or Google Workspace, look there first. Microsoft Purview retention policies keep a copy of mailbox items after users delete them, in the mailbox's Recoverable Items folder, where eDiscovery can still find them. Check which Microsoft 365 plan includes the parts you need. Google Vault handles retention, holds, search and export for Gmail and other Workspace data. Google says plainly that Vault is not a data archive: it keeps nothing until you set rules, and expired data that is not on hold is deleted as usual.

When MailVault is not the answer

We make MailVault, so here it is plainly: MailVault does not replace MailStore Server. It has:

• No central archive server and no archive shared between users.
• No admin access to other people's mailboxes, and no journaling.
• No retention policies, legal hold, audit trail or auditor role.
• No PST import.

If an auditor, a regulator or your legal team will ask questions about your company's email, choose one of the server options above.

Who MailVault does fit

Many people who search for a MailStore Server alternative do not need a server at all. They are one person with a full mailbox, a freelancer who wants every client thread kept, or a team of three where each person looks after their own inbox. For them a server is extra work: a machine to run, updates to apply, and a backup of the archive itself.

MailVault is a free desktop app for macOS, Windows and Linux. Each person installs it, signs in to their own Gmail, Microsoft 365, Outlook.com or IMAP account, and keeps a copy of their mail on their own computer. There is no MailVault account and no MailVault server in the path of the mail, and the source is live on GitHub. The email archiving guide for freelancers and small businesses covers that case in more detail.

What MailVault does

A local archive in plain files

Every message you keep is a standard .eml file in Maildir-style folders, one file per email, so other mail apps can open it. The vault can move to an external drive or a NAS mount: MailVault copies everything, checks that every file arrived, and only then removes the originals. That move is not available in the Mac App Store edition. A backup run can also write a second copy to a folder you choose.

Search on your own computer

A local full-text index searches every saved message, with or without a connection. You can narrow by sender, date, folder or tag. In our published search test, the slowest search across 50,000 messages took 14 milliseconds. Searching inside PDF and Office attachments is a Premium feature.

Backups

Manual backups of every account are free and unlimited. Scheduled backups, with server, local and external counts per folder, are part of Premium.

Archive, then delete, with a check in between

Archive copies mail into your vault and leaves the server copy alone. Delete from Server removes the server copy. Both are free. Archive & Delete (Premium) does both in one step: it copies each message into your vault, checks that the copy is there, and only then deletes it from the server. Anything that fails the check stays on the server. Archive, Back up & Delete (Premium) also writes a copy to your backup folder and checks both copies before anything is removed.

A small-team setup without a server

For a team of two to five people where nobody needs to search a colleague's mail, this is enough:

1. Each person installs MailVault and adds their own account.
2. Each person picks a second-copy folder on a drive they control, such as an external SSD or a NAS share, in Settings, Backup & Restore.
3. Run a backup, then archive the older years. Delete from the server only what is in the vault. On Premium, Archive & Delete does that check for you.

What you give up: one person cannot search another person's archive, and there is no central record of who did what. If you need either, you need a server.

Frequently asked questions

What to do next

If the requirement is compliance, start a trial of a server product, or put Piler or Mail-Archiver on a test machine and archive one mailbox. If it is one mailbox per person, download MailVault free and try it on one account first. Premium costs $4 a month or $25 a year at early-access prices (see pricing) if you later want scheduled backups or one-step Archive & Delete.

Related: a MailStore alternative for Mac, MailVault vs MailStore Home and seven MailStore alternatives compared.