Where apps hide your files

Finding the Outlook for Mac profile folder

Updated 2026-10-28 · 6 min read

Outlook for Mac keeps your mail cache, contacts and signatures in a hidden profile folder inside Group Containers. Here is the exact path, what sits inside it, and the safe ways to back it up or get a copy out.

The location

For Outlook 2016 and later on a Mac, including Outlook for Microsoft 365, which is what Microsoft's article covers:

~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile

That is Microsoft's own path. Its support article says Outlook caches your mail "in a profile in your home folder" at ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles, and Microsoft Q&A answers place the default profile in a subfolder called Main Profile. A second profile, if you ever made one, gets its own folder beside it.

Finder hides your Library folder. To reach the profile, press ⇧⌘G (Go > Go to Folder), paste the path above, or open the parent folder from Terminal:

open ~/Library/Group\ Containers/UBF8T346G9.Office/Outlook/Outlook\ 15\ Profiles

What is inside Main Profile

On the Mac used for this guide, a legacy Outlook profile holds these items. Names and sizes were listed, nothing was opened.

Item	What it is
Data	The legacy Outlook database and its pieces (about 24 MB here)
Data/Outlook.sqlite	The main database, with -shm and -wal companion files beside it
Data/Messages	Message files with the extension .olk15Message, in numbered subfolders
Data/Message Sources	Raw copies of messages, extension .olk15MsgSource
Data/Folders, Contacts, Categories, Saved Searches	Folder, contact, category and search definitions
Data/Signatures	Your signatures, covered in a separate post
Files	Undocumented file storage (324 KB here)
HxStore.hxd, hxcore.hfl	Files whose names match the new Outlook's engine (12 MB for HxStore.hxd here)
ProfilePreferences.plist	Per-profile preferences

Microsoft does not document the internal layout, so treat the table as an observation about one Mac, not a specification. The Hx files appearing beside the legacy Data folder suggests new and legacy Outlook share the profile folder, but Microsoft does not say so.

Local copy, not the mail itself

Microsoft says Outlook for Mac is intended to be a "purely locally cached" mail client. For an Exchange, Microsoft 365, Outlook.com, Gmail or IMAP account, the server holds the real mailbox and the profile holds a cache of it, so a lost profile is usually recoverable by signing in again. Folders under On My Computer are different: those exist only on your Mac (Microsoft's import article puts imported archives there too), so back them up before you touch anything.

Other Outlook folders

• Preferences: ~/Library/Containers/com.microsoft.Outlook/Data/Library/Preferences/com.microsoft.Outlook.plist. Settings, not mail.
• Shared Office data: ~/Library/Group Containers/UBF8T346G9.Office also holds OutlookProfile.plist, Outlook/Outlook Sound Sets and User Content.localized, where Office templates live.
• Logs and caches: inside ~/Library/Containers/com.microsoft.Outlook/Data/Library.

Moving the profile

Microsoft says not to. Its support article states that changing the default Profile folder location to an external disk or a network is not recommended, and that a profile kept there is not supported. A symlink to another drive has been reported on Apple's forums to launch Outlook and then freeze (a user report, on Outlook 2016). If space is the problem, work out what is taking it first (du -sh on the folders above) and clean up inside Outlook.

Old and new Outlook

Outlook for Mac has two interfaces. The legacy one has a Tools tab and the Export to Archive File (.olm) option. Microsoft's export and import articles are written for legacy Outlook only, so check the menus of your own version before relying on an .olm export from the new Outlook. Microsoft's end-of-support page says legacy Outlook for Mac stops working with Exchange Online mailboxes from October 2026, because the Exchange Web Services it relies on are retired on October 1, 2026, and keeps working with on-premises Exchange until October 9, 2029. The timeline differs by licence, so check that page for yours.

If you still use the legacy interface and want a portable copy, export before you switch.

Export a copy the supported way

In legacy Outlook for Mac, Microsoft's steps are:

1. On the Tools tab, choose Export. If you do not see it, update Outlook from the Help menu, or look on the File menu.
2. In the Export to Archive File (.olm) box, tick the items to export and choose Continue.
3. In Save archive file as, pick a folder such as Downloads and choose Save.
4. When the notification appears, choose Finish.

Microsoft says .olm is the only export format. Its page does not say whether signatures are included, and it does not describe export in the new Outlook. An .olm file holds a lot of mail, so keep it somewhere private.

Backing up or moving to a new Mac

Quit Outlook first. Then copy the whole Outlook folder from the Group Containers path above to an external drive. This is a safety copy, not a supported restore: people on Microsoft Q&A and Apple's forums report that putting the folder back does not always make Outlook see the old data, and one answer suggests replacing the Outlook folder with the backed-up one only after quitting Outlook. Never put a copied profile back while Outlook is open. A new Mac signing in to the same mail accounts rebuilds its cache from the server, which is the dependable route for server-based accounts. For local-only folders, Microsoft's route is the .olm export, then on the new Mac Tools > Import, Outlook for Mac archive file (.olm), Continue; the imported items appear under On My Computer.

For automatic backups Microsoft points to Time Machine, which includes ~/Library, so the profile is in your backups unless you excluded it.

Why a normal search misses it

The profile sits in ~/Library/Group Containers, a protected hidden location. Spotlight and Finder searches leave it out. The files are named by generated IDs, so a subject line or sender will not match a file name either.

Finding the files again

Typing olk15Message or Outlook.sqlite into Everywhere lists the profile's files wherever they sit, including inside Group Containers, which it indexes once it has Full Disk Access. Typing Outlook 15 Profiles jumps to the folder itself, and ⌘↵ reveals the selection in Finder. It matches file names only, so it will not search inside messages.

Common questions

Where is the Outlook profile on a Mac?

At ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile. Microsoft documents the Outlook 15 Profiles folder, and the default profile is the Main Profile folder inside it.

Can I move the Outlook for Mac profile to an external drive?

Microsoft says this is not recommended and that a profile on an external disk or network location is not supported. Free space another way.

How do I export Outlook for Mac mail to an .olm file?

In legacy Outlook for Mac, choose Export on the Tools tab, tick the items, choose Continue, then pick where to save it. Microsoft's page describes this only for legacy Outlook, not the new one.

Is my Outlook mail stored on my Mac?

For server accounts the profile is a local cache of the mailbox, which Microsoft describes as a locally cached client. Folders under On My Computer exist only on your Mac.