Back Up Your Outlook Data
Open Outlook.
Select File.
Go to Open & Export > Import/Export.
Select Export to a file, then click Next.
Select Outlook Data File (.pst).
Choose the email account you want to back up.
Select Include subfolders.
Choose where to save the backup file.
Click Finish.
Keep the .pst file in a safe location, such as an external drive or secure cloud-storage folder.
Restore Your Outlook Data
Open Outlook.
Select File.
Go to Open & Export > Import/Export.
Select Import from another program or file.
Select Outlook Data File (.pst).
Locate and select your backup file.
Choose how Outlook should handle duplicate items.
Select the folder you want to import.
Click Finish.
Your emails, contacts, and calendar items will be imported into Outlook.
Important: Importing a .pst file is currently supported in classic Outlook, but not in the new Outlook for Windows. If you use the new Outlook, switch to classic Outlook before restoring your backup.
For additional information, see Microsoft’s official guides for exporting Outlook data and importing a PST file.