How to Back Up Outlook Emails (Export to a PST File)
If your email is in Microsoft 365, Outlook.com or Gmail, it's already stored on the provider's servers — but "already on a server" isn't the same as "backed up". Accounts get closed, work mailboxes get deleted when you leave, and sometimes you just want a copy you control. A .pst file is Outlook's portable archive: one file holding emails, contacts and calendar that you can keep, copy or open later.
Quick reference
| What you want | How |
|---|---|
| Export to .pst | Classic Outlook: File → Open & Export → Import/Export |
| Outlook.com mailbox | Settings → General → Privacy and data → Export mailbox |
| Open a .pst later | File → Open & Export → Open Outlook Data File |
| New Outlook | Can open .pst files; export needs classic Outlook |
1. Export to a .pst file (classic Outlook)
1. Click File → Open & Export → Import/Export.
2. Choose Export to a file and click Next.
3. Choose Outlook Data File (.pst) and click Next.
4. Select the account name at the top of the list to export everything — email, calendar, contacts and tasks. Make sure Include subfolders is ticked. (Or pick just the Inbox or one folder.)
5. Click Next, then Browse to choose where to save it — your Documents folder, an external drive or OneDrive.
6. Choose Replace duplicates with items exported, click Finish.
7. You can set a password on the file; leave it blank if you don't want one, and click OK.
2. Choose Export to a file and click Next.
3. Choose Outlook Data File (.pst) and click Next.
4. Select the account name at the top of the list to export everything — email, calendar, contacts and tasks. Make sure Include subfolders is ticked. (Or pick just the Inbox or one folder.)
5. Click Next, then Browse to choose where to save it — your Documents folder, an external drive or OneDrive.
6. Choose Replace duplicates with items exported, click Finish.
7. You can set a password on the file; leave it blank if you don't want one, and click OK.
Outlook creates the file. A big mailbox can take several minutes. The file size roughly matches your mailbox size — a 10 GB mailbox gives a 10 GB file.
2. Export an Outlook.com mailbox (new Outlook / web)
New Outlook can't create .pst files yet, but Outlook.com, Hotmail and Live accounts can be exported from the web:
1. Sign in at outlook.com and click Settings → General → Privacy and data.
2. Click Export mailbox.
3. Microsoft prepares a .pst file — this can take up to four days for a large mailbox. You'll get an email with a download link when it's ready.
2. Click Export mailbox.
3. Microsoft prepares a .pst file — this can take up to four days for a large mailbox. You'll get an email with a download link when it's ready.
For a Microsoft 365 work account in new Outlook, either switch to classic Outlook for the export or ask IT — admins can export mailboxes centrally.
3. Keep the backup safe
A .pst file on the same computer as Outlook is only half a backup. Copy it to:
• an external drive you keep somewhere else, and/or
• OneDrive or another cloud folder.
• OneDrive or another cloud folder.
Don't open the .pst from inside OneDrive while Outlook is running — Outlook locks the file, which upsets syncing. Copy it in and out instead.
Repeat the export every few months, or before you leave a job (check your company's policy on what you're allowed to take).
4. Open a .pst file later
Classic Outlook: File → Open & Export → Open Outlook Data File, choose the file. It appears in the folder list as a separate section; browse it like any other mailbox. Close it by right-clicking → Close "Outlook Data File".
New Outlook: Settings → Accounts → Email accounts → Add account → Add Outlook data file (.pst) and browse to the file.
5. Import a .pst into a new account
Moving to a new computer or a new email address? File → Open & Export → Import/Export → Import from another program or file → Outlook Data File (.pst), then choose the destination account. Everything copies into the new mailbox.
Troubleshooting
The Import/Export option is missing. You're in new Outlook. Toggle to classic Outlook (top right) for this job, or use the Outlook.com export.
The .pst is huge. Export only your Inbox and Sent Items, or exclude folders with large attachments. You can also set an Archive policy in File → Info → Tools → Clean Up Old Items to move old mail to a separate .pst.
Outlook says the file is corrupt. Run ScanPST.exe (search your PC for it; it's in the Office folder) against the file to repair it.
Wrapping up
Export to .pst every few months, keep a copy on a drive that isn't your computer, and you'll never lose ten years of email to a closed account or a dead hard drive.
