Mail is the one service where “the provider handles it” turns out to be only half true. Hosted mailboxes are delivered and stored for you; they are not archived for you in any sense that survives a deleted account, an expired retention window or a contract ending. And if you run your own mail server, everything is yours — including the part where you have to make it work.
This guide covers the free mail software on this site: archiving what you already have, and running a server if you decide to.
What is available free
| Tool | Role | Licence condition |
|---|---|---|
| MailStore Home | Archives mail from clients and servers into a searchable local store | Free — personal use only, not company mailboxes |
| hMailServer | A full mail server for Windows | Free and open source |
| Mail-in-a-Box | A complete mail server built for you on a fresh Ubuntu machine | Free and open source |
| IceWarp | A commercial mail and collaboration platform | Conditionally free |
Archiving: MailStore Home
MailStore Home pulls mail out of Outlook, Thunderbird, IMAP and POP accounts and PST files into a single compressed, searchable archive on your own disk. Search across every account at once is the part people keep it for.
The licence is the catch and it is not ambiguous: MailStore Home is for personal use. Archiving company mailboxes — including your own work mailbox, and certainly shared or role accounts — is not covered. The vendor sells a separate server product for that. If you are archiving a business, budget for it rather than hoping nobody checks.
For a personal archive, or for a retired mailbox you want to keep readable after the account is gone, it does exactly what it says.
Running your own mail server
Two free routes, and they suit very different people.
hMailServer — Windows, assembled by you
hMailServer is a mail server for Windows with SMTP, POP3 and IMAP, virtual domains, aliases, rules and anti-spam hooks. It is free and open source and it has run small company mail for years.
Two things to know before you commit. The 5.7 branch is 64-bit only, and its recent builds are labelled pre-release — you will be running software the author has not declared final. And hMailServer is a mail server, not a mail system: you supply the webmail, the antivirus, the backups and the DNS records yourself.
Mail-in-a-Box — everything, on its terms
Mail-in-a-Box takes the opposite approach. You give it a fresh machine and it builds a complete mail system: SMTP, IMAP, webmail, contacts and calendar, spam filtering, DNS, certificates and backups, configured to current standards.
The condition is absolute and deliberate: a dedicated machine running the supported Ubuntu version, and no manual configuration afterwards. Mail-in-a-Box owns the configuration. If you edit it by hand, the next update overwrites your work. Accept that and it is the fastest route to a correctly configured mail server that exists. Fight it and you will have a bad time.
Before you self-host, be honest about deliverability
Running a mail server is not hard. Getting large providers to accept your mail is. Budget for:
- SPF, DKIM and DMARC correctly published — not optional in 2026, and the most common reason new servers land in spam.
- A clean IP address with proper reverse DNS. Cheap hosting ranges are often already on blocklists, and you inherit their reputation.
- TLS certificates that renew automatically.
- Monitoring of the queue. A mail server that stops delivering rarely announces it — NetXMS or EventSentry Light can watch the service and the disk it writes to.
- Log retention. When someone insists they sent a message, the log settles it. Graylog keeps it searchable; LogExpert reads it when you just need the file.
- Backups that include the message store and the configuration, tested by actually restoring — see off-site backup.
None of that is a reason not to self-host. It is a reason not to self-host by accident.
Hosted mail still needs an archive
Whatever platform you rent, three things are true: deleted items leave the recycle bin on a schedule you do not control, a closed account usually takes its mailbox with it, and retention policy is not backup. An independent archive is the only copy that survives all three. For a company that means a licensed archiving product; for personal mail, MailStore Home covers it.
FAQ
Can I use MailStore Home for work email?
No. The free edition is licensed for personal use only; business mailboxes need the vendor’s paid product.
What is the best free mail server for Windows?
hMailServer. Note that the 5.7 branch is 64-bit only and its current builds are marked as pre-release.
Can I install Mail-in-a-Box on an existing server?
No. It requires a dedicated machine running the supported Ubuntu version and manages the whole configuration itself.
Is Microsoft 365 or Google Workspace mail backed up?
Not in the sense of a restorable copy you control. Retention policies and the recycle bin are time-limited and do not survive a deleted account.
Why does mail from my new server go to spam?
Almost always missing or wrong SPF, DKIM and DMARC records, or an IP address with poor reputation and no reverse DNS.
