How to Import Archive Emails in Outlook: Full Guide

To import archived emails into Outlook for Windows, open classic Outlook and choose File > Open & Export > Import/Export, then import the Outlook Data File (.pst) into the mailbox or folder you want. You will need access to the archive file and the Outlook profile where the messages should go. If your archive is already an Online Archive mailbox, you usually do not need to import it; expand that archive in the folder list instead.

What You’ll Need

The archive file: Most local Outlook archives use the .pst extension. Know where the file is saved, such as Documents, an external drive, or a shared folder. Outlook must be able to access it throughout the import.
Classic Outlook for Windows: The full Import/Export wizard described below is in classic Outlook for Microsoft 365. New Outlook has a different feature set and may not show this wizard. If necessary, switch to classic Outlook using the toggle in the upper-right corner, if it is available, or open classic Outlook from the Windows Start menu.
The correct Outlook account and enough space: Decide whether to copy messages into your mailbox or into a separate data file. A large import into a work or school mailbox may take time to upload and may be limited by the mailbox quota.
The PST password, if applicable: Outlook will prompt for it if the archive is password-protected. A file password is separate from your Microsoft 365 account password.

Step-by-Step

Confirm what kind of archive you have. In File Explorer, check the file extension. A .pst file is the usual Outlook archive format and can be imported using the steps below. An .ost file is an offline cache associated with an account, not a standard archive to import; reconnect to the original account or ask your administrator about recovering its contents. If you see individual .eml files or a compressed ZIP folder, extract or convert them using an appropriate supported method first; the PST Import/Export wizard does not import a folder of EML files as an archive. If the archive is an Exchange Online Archive already listed under your account in Outlook, expand it rather than importing it again.
Make a safe copy of the PST. Close any other Outlook windows that might be using the file, then copy the PST to a drive or folder you can access reliably. Avoid importing directly from a removable drive that may disconnect or from a cloud folder that is still syncing. Keep the original unchanged until you have confirmed that the imported mail is complete. If the file is stored on a network share, copying it locally first can reduce interruptions.
Open the Outlook profile that should receive the messages. Start classic Outlook and check the account name and folders in the navigation pane. If you have several accounts or profiles, make sure the intended mailbox is open. For a work mailbox, consider whether the imported messages belong in the main Inbox structure, a dedicated folder, or a local data file. Importing into a mailbox can upload the messages to the mail server, so check available storage before proceeding with a very large archive.
Start the Import/Export wizard. In classic Outlook for Windows, select File > Open & Export > Import/Export. In the wizard, select Import from another program or file, then select Next. Choose Outlook Data File (.pst) and select Next again. These are the classic Outlook ribbon and backstage menu names; if you cannot see File or Import/Export, you may be using new Outlook rather than classic Outlook.
Choose the PST and duplicate-handling option. Select Browse, locate the .pst file, select it, and choose Open. Under Options, choose what Outlook should do if it finds an item that already exists in the destination: replace duplicates with imported items, allow duplicates to be created, or do not import duplicates. If you are unsure, Do not import duplicates is often the cautious choice for a repeat import, but it can also skip an older item Outlook considers a duplicate. If this is the first import and you want to preserve all items, choose the option that matches that goal. Enter the PST password if prompted, then select Next.
Select the folders and destination. In the folder tree, select the top level of the PST to bring in all its folders, or select a specific folder such as Inbox, Sent Items, or a custom archive folder. Leave Include subfolders checked if you want Outlook to import the folder structure beneath your selection. Under Import items into the same folder in, choose the destination account or data file from the list. For example, importing the PST Inbox into the mailbox normally places those messages in that mailbox’s Inbox; custom folders are brought across as corresponding folders. Check the destination carefully before continuing, especially if multiple accounts have similar names.
Run the import and verify the result. Select Finish and let Outlook complete the operation. A large archive may take a while, and importing to a Microsoft 365 or Exchange mailbox may be followed by a separate upload and synchronization period. When Outlook has settled, expand the destination folders, open several older and newer messages, and check attachments and subfolders. Search for a distinctive sender or subject to confirm that expected mail arrived. Keep the original PST until you are satisfied with the result and any mailbox upload has finished.

If you only need to read or search a PST without copying its contents into another mailbox, you can open it as a separate data file instead: in classic Outlook, choose File > Open & Export > Open Outlook Data File, select the PST, and open it. Its folders should appear in the folder pane. Opening a PST is not the same as importing it: the file remains separate, and its contents are not automatically copied into your account.

Common Mistakes

Confusing a local PST with an Online Archive: A PST is a file on a drive. An Online Archive is a mailbox feature hosted by Exchange and appears as an archive folder tree in Outlook. Importing an Online Archive’s contents again can create duplicates.
Choosing the wrong destination: The wizard can import into another account or data file if you select it. Read the destination name before finishing, particularly when personal and work accounts are open together.
Importing everything when only one folder is needed: Selecting the PST’s top-level folder imports its folders and, with subfolders included, potentially its entire contents. Select only the specific folder you need if you want a smaller, quicker import.
Assuming a PST is a live backup: Changes made to imported messages do not update the original PST. Likewise, opening a PST does not merge it with the mailbox. Keep a separate backup if the archive is important.
Deleting the source too soon: An import may appear complete in Outlook while a cloud mailbox is still synchronizing. Do not remove the source PST until the folders, messages, and attachments have been checked and the destination is accessible.
Repeatedly importing without considering duplicates: Running the wizard again can create repeated messages if you selected the option to allow duplicates. Choose the duplicate setting deliberately and check the destination before repeating an import.

Tips

Use a dedicated folder for a large archive. Instead of mixing old mail into a crowded Inbox, consider creating a clearly named folder such as “Imported archive 2022” in the destination mailbox, then select or organize the imported folders there. This makes the imported material easier to find and review.
Check mailbox storage first. A PST may be larger than the space available in a work or school mailbox. Importing locally into a separate Outlook data file avoids uploading the content to the server, but that data file may then be available only on the computer where it is stored. Ask your administrator about mailbox limits and retention requirements for a managed account.
Use a wired or stable connection for cloud mailboxes. The wizard can finish before every imported item has synchronized to Microsoft 365 or Exchange. Leave Outlook open and connected, and allow time for the upload, especially with large attachments or many folders.
Keep folder structure where it helps. Leaving Include subfolders selected preserves nested folders, which is useful when the archive was organized by year, project, or client. If you want a flatter structure, select only the folders you need rather than importing the whole tree.
On Outlook for Mac, use its own import workflow. The Windows instructions and ribbon paths do not apply on Mac. In supported Outlook for Mac versions, look under File > Import and follow the prompts for an Outlook for Windows archive (.pst) if that choice is offered. Import options can vary by Outlook version and account type; if PST import is unavailable, use classic Outlook for Windows or consult your organization’s support team.
Keep privacy and retention in mind. An imported message can contain sensitive information and may become subject to your organization’s mailbox retention, legal hold, or sharing policies. For a business account, check with the administrator before moving personal or regulated archives into it.

Troubleshooting

The Import/Export option is missing. The most common reason is that Outlook is in the new Outlook interface. Switch to classic Outlook if the toggle is available, or launch the classic Outlook app from Start. In new Outlook, PST features and import availability can differ by build and account, so do not follow a menu path that is not present in your version.

Outlook says the file cannot be opened or is not a PST. Confirm the file ends in .pst and that it has finished copying or downloading. A renamed file is not necessarily a valid PST. If it is actually an OST, EML, or ZIP file, use the correct recovery or extraction method rather than changing its extension. If a valid PST appears damaged, work from a copy and use Outlook’s available repair tools or contact your administrator before attempting recovery.

The password is rejected. Check that you are entering the PST file password, not your email sign-in password. Confirm the keyboard layout and Caps Lock, and ask the person who supplied the archive for the correct password. Outlook cannot bypass an unknown PST password.

Some mail or folders are missing. Reopen the PST separately with File > Open & Export > Open Outlook Data File and inspect its folder tree. The import may have been limited to a selected folder, or Include subfolders may have been unchecked. Check the duplicate rule too: Outlook may have skipped items it identified as duplicates. If you rerun the import, choose the folders and duplicate option carefully to avoid creating a second set.

The import seems stuck or Outlook is slow. Large PSTs and archives with many attachments can take time to process. Keep Outlook open, make sure the computer is not running out of disk space, and avoid disconnecting the drive containing the PST. If Outlook becomes unresponsive for an extended period, wait before closing it; then reopen Outlook and inspect the destination before deciding whether to retry. Do not repeatedly launch the wizard while the first import may still be running.

The messages appear in Outlook on the computer but not elsewhere. If you imported into a local Outlook Data File, that content is stored in the PST on that computer and will not automatically appear in webmail or on a phone. To make messages available across devices, import them into the appropriate server mailbox, provided it has enough capacity and your organization allows it. Then leave Outlook online until synchronization completes.

Frequently Asked Questions

Can I import an archive without deleting or changing the original PST?
Yes. The import copies items into the selected destination; it does not normally remove them from the source file. Keep the original as a backup and verify the copied content before deleting or moving anything.

Can I import a PST into Outlook on the web?
The classic Outlook Import/Export wizard is a desktop feature, not a general Outlook on the web menu. Import the PST using supported desktop Outlook, then allow the destination mailbox to sync so its contents can appear online.

Will importing archive emails create duplicates?
It can. In the wizard, choose whether to replace, allow, or skip duplicate items. The choice matters most when importing the same PST more than once or when some of its mail is already in the destination.

Can I import only one folder from the archive?
Yes. In the folder-selection screen, select the specific folder you want rather than the PST’s top level. Leave Include subfolders checked only if you also want the folders nested beneath that selection.

Why can I see an archive in Outlook but not find a PST file?
You may be looking at an Online Archive mailbox hosted by Exchange rather than a local archive file. Expand the archive in the folder pane and check whether its messages are already available. If it is missing, contact your work or school administrator to confirm that the feature is enabled for your account.

Does importing a PST move my mail onto every device?
Only if you import it into a mailbox that synchronizes with those devices and allow the upload to finish. Mail imported into a local data file remains local to that Outlook setup unless you take additional supported steps to move it into a server mailbox.

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