How to back up your Outlook emails to protect your data

Outlook isn’t just for emails. It also has an address book, a calendar, scheduling functions, and a journal, all combined in a single user-friendly interface. Contacts, meetings, and projects are synchronized and networked across all these features, but this comes with a risk. In the event of a hardware or software failure, you could lose a lot of data as everything is stored centrally. To protect your financial and personal data, it’s therefore a good idea to save important data and emails in an Outlook backup. Let’s take a closer look at how to do this.

How does Outlook manage emails?

To understand how to protect your Outlook user data, you first need to know how Outlook manages it. There are two different types of Outlook account:

  • Outlook POP accounts (including POP3): The original Outlook data is downloaded from the server and stored on a local machine in PST format.
  • Exchange, IMAP, Outlook 365, or accounts: Data is only stored on the local device temporarily, in OST format. The original data remains on the server.

So what’s the difference between the two Outlook file types, PST and OST?

  • PST files: PST stands for Personal Storage Table. This Outlook file format acts like a data container and can only be used and opened via an Outlook account. Personal, synchronized user data is sorted into folders, then downloaded from the server and stored locally in PST format. An initial PST file is created automatically when you set up an Outlook POP account. However, PST files can also be saved both automatically and manually, and you can also split them up, for example to separate personal emails from business emails. The advantage of PST format is that the files can be up to 50 GB in size, meaning that you can create large Outlook email archives.
  • OST files: OST stands for Offline Storage Table. As the name indicates, these are offline files, and they are only stored on the local machine temporarily. The original files remain on the Exchange server, so they are automatically stored as an Outlook backup. If you make changes to the local OST files, Outlook will synchronize them automatically when you next log in. The advantage of OST format is that you can access your data even if you are offline. In Outlook 2010 and earlier, Outlook used the PST format for temporary files. OST became the standard temporary format in Outlook 2013.

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What kind of data can you save in an Outlook backup?

Outlook data backups are always created in PST format. This is a proprietary Microsoft format that Outlook uses to import and export data. When creating an Outlook backup, you can include emails, contacts and addresses, calendar data, journal entries, and also various settings such as categories and filters. Exporting a PST file serves two purposes. It gives you a local copy of your data, and you can also use it to import your Outlook data and contacts and transfer your settings if you change device or account.


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How to back up Outlook emails: a step-by-step guide

The fastest way to back up your Outlook emails and data is to export a PST file and save it on your computer or an external storage device. Here’s how:

Step 1: In the Outlook “File” tab, select “Open & Export”, then click on “Import/Export”.

Step 2: In the Import and Export Wizard, select the “Export to a file” action and click on “Next”.

Step 3: In the next window you will be asked to choose the file type for your Outlook backup. Select “Outlook Data File (.pst)”.

Step 4: Now choose the data you want to export. In this example, we’re going to back up the “Calendar” folder. Select “Include subfolders” so that your backup will include any subfolders, then click on “Next”.

Step 5: Finally, choose where you want to save the backup file. This can be either a local folder, an external hard drive, or a USB stick for example. For important data, it’s worth saving identical backups on multiple storage devices wherever possible. If you create Outlook data backups regularly, you can select the “Replace duplicates with items exported” option to avoid duplicate files. Click on “Finish” to exit the wizard.

Quick-reference guide to Outlook backups

Step 1: In Outlook, go to “File” > “Open & Export” > “Import/Export”.

Step 2: In the Import and Export Wizard, click on “Export to a file”.

Step 3: Select “Outlook Data File (.pst)”, then click on “Next”.

Step 4: Choose the files or folders to include in the export. To include subfolders too, select “Include subfolders”.

Step 5: Specify where you want the exported file to be saved. To avoid creating duplicates, select “Replace duplicates with items exported”. Click on “Finish” to exit the wizard.


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Backing up Outlook emails and data on a cloud

Instead of – or as well as – creating a backup in PST format, you can save some of your user data using a cloud storage solution. That way you can access your data in a secure manner at any time, from any device. Backing up business data is a key part of digital archiving. It helps you organize tasks and contacts, reduces the amount of paper you use, and limits the risk of data loss.


The IONOS HiDrive cloud storage solution offers secure, centralized storage for up to 2,000 GB of data.

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