How Can I Back Up My Outlook Emails?

If you use classic desktop Outlook, the quickest way to back up your emails is to export them to a PST file. That saves a copy of your mailbox, or just the folders you choose, to your computer or an external drive. If your email runs on Microsoft 365 through work, the best option is a backup set up at mailbox level. That way every user is covered automatically and nobody has to remember to do it.

This guide covers both. It’s written for business owners, office managers and anyone looking after email for a team. We’ll go through the manual steps in Outlook and the options for Exchange and Microsoft 365 mailboxes. We’ll also explain why a one-off export is rarely enough once a business depends on its inbox.

Why Backing Up Email Matters for a Business

For most businesses, email is the record of everything: quotes, contracts, supplier agreements, customer conversations and approvals. If a mailbox is lost, you lose much more than messages. You lose the paper trail behind your decisions.

Emails go missing more easily than most people expect. Someone deletes a folder by accident, a member of staff leaves and their mailbox is removed, or a sync fault wipes items across devices. Then there’s cyber crime. 43% of UK businesses reported a cyber security breach or attack in the past year, and a compromised account can lead to deleted or encrypted mail.

A good backup means you can restore what you need quickly, whether that’s a single email or a whole mailbox, without paying a ransom or relying on luck.

Does Microsoft 365 Back Up My Emails?

This is one of the most common misconceptions we hear. Microsoft 365 keeps its service running and protects its own infrastructure, but it doesn’t back up your data the way most people assume.

When you delete an email, it goes to Deleted Items. Once it’s removed from there, it moves to a hidden Recoverable Items folder, where it’s kept for 14 days by default. An administrator can extend that to a maximum of 30 days. After that, it’s gone for good.

That’s a safety net for recent mistakes, not a backup. It won’t help if you discover a problem six weeks later, if a mailbox is deleted when someone leaves, or if you need to roll back after a ransomware attack. Looking after your data is your responsibility, which is why many businesses add a separate Microsoft 365 backup on top of the standard tools.

How to Back Up All Emails in Outlook

How you back up Outlook emails depends on which version of Outlook you use. Most businesses still use classic desktop Outlook, so we’ll start there. Then we’ll cover the new Outlook, the web version, and how to back up just the folders you need.

Export to a PST File (Desktop Outlook)

A PST file (Outlook Data File) holds a copy of your emails, calendar, contacts and tasks in one file. To back up all emails in classic Outlook for Windows:

1. Open Outlook and select File, then Open & Export, then Import/Export.
2. Choose Export to a file and select Next.
3. Select Outlook Data File (.pst) and select Next.
4. Click the email address at the top of the folder list to include the whole mailbox, and make sure Include subfolders is ticked. Select Next.
5. Select Browse to choose where to save the file and give it a clear name, such as your name and the date.
6. Select Finish. You can add a password to protect the file if you want to.

A large mailbox can take a while to export, so leave Outlook open until it’s finished. Once it’s done, save a copy of the file somewhere other than your computer, such as an encrypted external drive or a secure network location. A backup stored only on the same laptop won’t help if that laptop is lost, stolen or fails.

Back Up Emails in Outlook 365 and Office 365

If you’re wondering how to back up email in Outlook 365, the steps above are the same. “Outlook 365” usually means the desktop Outlook app that comes with a Microsoft 365 or Office 365 subscription.

The new Outlook for Windows can now export a whole mailbox or a single folder to a PST file as well, although the menus look different from classic Outlook. Outlook on the web has no PST export option, so you’ll need a desktop app or your IT administrator. On a Mac, legacy Outlook exports to an OLM file instead of a PST file, using Tools, then Export.

Some businesses switch off PST exports for compliance reasons. If you can’t see the option, your IT administrator may have turned it off.

Back Up Specific Folders

You don’t always need the whole mailbox. To back up a single folder, such as a client folder or an old project, follow the same export steps. At step 4, click the folder you want instead of your email address. Untick Include subfolders if you only want that folder.

You can also select Filter at the same step to export only certain emails, such as messages from a particular date range or sender. This keeps your backup files smaller and makes it easier to find what you need later.

How to Back Up Exchange and Microsoft 365 Mailboxes

Exporting a PST file works for one person. It doesn’t work well for a whole business. Exports depend on people remembering to run them, they capture a single moment, and they leave copies of company email on individual devices. For business accounts, a backup should run at mailbox level and be managed centrally.

Backing Up Microsoft 365 and Exchange Online Mailboxes

If your email runs on Microsoft 365, your mailboxes are hosted on Exchange Online. There are two main ways to back them up:

• Microsoft 365 Backup: Microsoft’s own pay-as-you-go service. It backs up Exchange Online mailboxes, OneDrive and SharePoint, and lets an administrator restore them to an earlier point in time.
• A dedicated Microsoft 365 backup service: a separate platform that copies your mailboxes to secure storage outside your Microsoft tenant, usually several times a day. Many of these services also cover Teams. Because the copy is kept separately, you can still recover your data if your Microsoft 365 account itself is compromised.

Whichever you choose, a good backup for Office 365 data should cover every mailbox automatically, including shared mailboxes, and let you restore anything from a single email to a whole account.

What Happens to a Mailbox When Someone Leaves?

This is where many businesses lose email without realising it. When a user account is deleted, or its licence is removed, the mailbox is only kept for 30 days. After that, it’s permanently deleted and can’t be recovered.

If you need to keep a leaver’s emails, back up the mailbox or convert it to a shared mailbox before you remove the account. Retention policies and holds can also preserve mailbox content for compliance. They’re useful, but they’re not a backup, because they’re designed for legal and regulatory purposes rather than quick, everyday restores.

How to Back Up an On-Premises Exchange Mailbox

Some businesses still run their own Exchange Server. In that case, backups happen at server level, using software that understands Exchange and can back up its databases safely while the server is running. Copying the files manually isn’t enough.

You should also test restores regularly. A backup is only worth having if you know it will work when you need it.

What Is Cloud Backup? Cloud Backup vs Local Backup

Once you’ve decided to back up your email, you need to decide where the backup is stored. There are two main options, and most businesses get the best protection by using both.

What Is Cloud Backup?

Cloud backup copies your data to secure servers run by a backup provider, away from your office and your own devices. It usually runs automatically on a schedule, often several times a day, so nobody has to remember to start it. If a laptop is lost, a server fails or your office is affected by fire or flood, your data is still safe and can be restored from anywhere with an internet connection.

For Microsoft 365 mailboxes, cloud backup is the natural choice. Your email already lives in the cloud, so backing it up to a separate cloud platform keeps everything off-site and easy to restore.

What Is Local Backup?

Local backup stores a copy of your data on hardware you control, such as an external hard drive, a network storage device (NAS) or a backup server in your office. A PST file saved to a USB drive is a simple example of a local backup.

Local backups are quick to restore from, because the data is close at hand and you don’t need to download it. The downside is that they’re exposed to the same risks as the rest of your office. Theft, hardware failure and ransomware can all affect a backup kept on the same network as the data it protects.

Cloud Backup vs Local Backup Compared

Why Most Businesses Use Both

Many IT providers recommend the 3-2-1 rule: keep three copies of your data, on two different types of storage, with at least one copy off-site. In practice, that often means your live data in Microsoft 365, a cloud backup held separately, and a local or offline copy for quick restores.

For a small business, a managed cloud backup alone is often enough for email. Businesses with large amounts of data, or tight recovery time targets, tend to add a local copy as well.

What Is Data Backup, and How Do You Back Up Company Data?

Email is only one part of the picture. Most businesses also rely on shared files, customer records, accounts and line-of-business software. If you’re putting a backup in place for Outlook, it makes sense to look at the rest of your data at the same time.

What Is Data Backup?

Data backup means making a copy of your information and storing it separately from the original, so you can restore it if the original is lost, damaged or locked by ransomware. A backup isn’t the same as a copy that syncs. If you delete a file from a synced folder such as OneDrive, it’s deleted everywhere. A proper backup keeps earlier versions, so you can go back to how things were before the problem happened.

Data Backup for Business: What to Include

A good business backup covers everything you’d struggle to work without. For most businesses, that includes:

• Email: every user mailbox and shared mailbox, including calendars and contacts.
• Files: OneDrive, SharePoint and any shared drives or file servers.
• Teams: chats, channel conversations and the files shared in them.
• Business applications: accounts, CRM and any industry-specific software, plus the databases behind them.
• Servers and devices: full system backups of any servers in your office, so they can be rebuilt quickly if they fail.

If you’re not sure what you have or where it’s stored, start by making a simple list. It’s common to find important data on a single laptop or in an old shared folder that nobody has checked in years.

How to Back Up Company Data

Why Manual Outlook Backups Are Not Enough for a Business

Exporting a PST file is a useful skill, and it’s fine for an individual or a one-off job. For a business, though, relying on manual exports leaves gaps that tend to show up at the worst possible moment.

• They depend on people remembering. Busy weeks happen, and backups get missed. The one time you need a backup is often the time nobody ran one.
• They’re out of date as soon as they finish. A PST file only holds emails up to the moment it was created. Anything after that isn’t protected.
• They don’t cover the whole business. Each person backs up their own mailbox, if they do it at all. Shared mailboxes, leavers’ accounts, OneDrive and Teams are easily missed.
• They create security risks. PST files hold complete copies of company email. Saved on laptops or USB drives without encryption, they can easily end up in the wrong hands.
• Nobody checks them. Large PST files can become corrupted, and you may not find out until you try to open one.

A managed backup takes these gaps away. Every mailbox is backed up automatically, several times a day, to secure storage kept apart from your Microsoft 365 account. Someone monitors the backups and fixes failures, and restores are tested so you know they’ll work.

Sentinel Data Solutions is Cyber Essentials Plus-certified and manages Microsoft 365 for businesses across the South of England. We can set up a backup that protects your email, files and Teams data, and keep it running so you don’t have to think about it.

Getting Started with Backing Up Your Business Email

If you only need a quick copy of your own mailbox, the PST export steps above will do the job. If you’re responsible for email across a team, it’s worth putting a proper backup in place before you need it.

Our team can review your current setup, explain the options in plain English and get a managed backup running with minimal disruption to your day. Get in touch to talk to our team about protecting your business email.