You open Outlook. It hangs for 12 seconds. Then a pop-up: 'Outlook cannot open this data file.' You try to remove it from Account Settings — but the option’s grayed out. You search online, copy-paste three different 'how to delete outlook data file' tutorials, and end up with a broken profile and missing calendar entries from 2021. This isn’t rare. It’s the default outcome when you treat a PST like a Word doc.
Quick Answer
You can delete an Outlook data file — but only after detaching it from your profile, closing Outlook completely, and verifying no other app (like OneDrive, Teams, or a backup tool) has it locked. Just deleting the .pst or .ost file from File Explorer while Outlook is running — or even idle — risks corruption, sync loss, or startup failures. The safest path is File > Account Settings > Account Settings… > Data Files tab > Remove, then manual file deletion after restarting Outlook once.
All the Methods
| Method | Steps | Best For | Limitations |
|---|---|---|---|
| Remove via Data Files tab | File > Account Settings > Account Settings… > Data Files tab > select file > Remove | Most users — especially those with multiple PSTs or archived mail | Doesn’t delete the physical file. Leaves .pst on disk unless manually removed later. |
| Manual deletion (after detachment) | Detach in Data Files tab → restart Outlook → locate file (usually in %USERPROFILE%\Documents\Outlook Files\ or AppData\Local\Microsoft\Outlook\) → delete .pst/.ost | Users cleaning up old archives or migrating profiles | Fails if Outlook or another process holds a lock. Requires knowing exact file location — not shown in UI. |
| Profile reset (Control Panel) | Control Panel > Mail > Show Profiles > select profile > Remove → re-add accounts | When OST is corrupted or syncing endlessly | Deletes all local cache — forces full mailbox re-sync (hours for large mailboxes). Shared mailbox delegates lose cached access until re-added. |
| Registry edit (advanced) | HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Profiles\[ProfileName]\00190300 → delete matching key | Power users who need to clean orphaned references after failed detachments | High risk of profile breakage. Only safe after full backup and with Outlook closed. Not supported in Outlook 365 Click-to-Run builds. |
| Outlook Web App (OWA) limitation | No ability to manage PST/OST files — OWA uses server-side data only | Users confusing cloud mail with local storage | You can’t ‘delete outlook data file’ from OWA at all — it doesn’t exist there. |
Method Details
How to delete the outlook data file — step-by-step (the right way)
This covers how to delete my outlook data file, how to delete an outlook data file, and how to get rid of outlook data file — all the same core process. Start here.
First: Open Outlook. Go to File > Account Settings > Account Settings…. Click the Data Files tab. You’ll see every PST and OST attached to this profile — including ones you didn’t knowingly add (e.g., ‘Archive’ or ‘Personal Folders’).
Select the one you want gone. Click Remove. A warning appears: 'This action will remove the data file from this profile but will not delete the file from your computer.' That’s critical. Click Yes.
Now close Outlook fully. Check the system tray — right-click the Outlook icon and choose Exit if it’s still running. Then restart Outlook. Confirm the file no longer appears under Data Files.
Only now should you delete the actual file. Press Win + R, type %USERPROFILE%\Documents\Outlook Files\, hit Enter. Or for OST files, try %LOCALAPPDATA%\Microsoft\Outlook\. Look for filenames ending in .pst or .ost. Match the name you saw in the Data Files tab (e.g., Archive2022.pst). Delete it.
Surprising tip: If you can’t find the file, go back to the Data Files tab, right-click the entry, and choose Open File Location. This works in Outlook 365 (build 2308+) and Outlook 2021 — but not in 2019 or earlier. In older versions, you’ll need to check the file properties instead: double-click the entry → click Settings → look for ‘Filename’ near the bottom.
How to delete old outlook data file — and why timing matters
This answers how to delete old outlook data file and how to clear outlook data file. ‘Old’ usually means archive PSTs from pre-2020, or duplicate OSTs created during laptop repairs.
Don’t assume ‘old’ = safe to delete. Check what’s inside first. Right-click the PST in Data Files → Open Folder → double-click the file in Windows Explorer. Outlook will mount it as a separate set of folders. Scan for anything you might need — maybe that ‘Budget Review Q3’ email from 2018, or ‘1:1 with Manager’ notes you never migrated to OneDrive.
If you’re using a shared mailbox, note this: removing its associated PST won’t affect other users. But if you added it as a delegate and cached it locally, deleting the PST breaks offline access to that mailbox — until you re-add it. There’s no central sync flag; each client manages its own cache.
For OST files specifically: you can delete outlook data files like OSTs — but Outlook regenerates them automatically on next launch. So unless the OST is corrupted (spinning ‘Processing’ forever), deleting it is rarely useful. Better to use File > Account Settings > Account Settings… > Email tab > Change > More Settings > Advanced > Offline Folder File Settings > Rebuild.
Can you delete outlook data files? Can i delete outlook data file?
Yes — but with caveats. Can you delete outlook data files? Technically yes. Can i delete outlook data file? Only if it’s not your primary mailbox file (the one tied to your Exchange account). Outlook won’t let you remove the main OST — it’s locked by design. You’ll see ‘Remove’ grayed out for that entry.
The real question isn’t permission — it’s consequence. Deleting a PST that contains your only copy of years of project emails? Risky. Deleting an OST? Harmless — it rebuilds. Deleting the wrong file while Outlook is open? That’s how you get ‘Cannot start Microsoft Outlook’ errors on Monday morning.
In Outlook 365 (cloud-first deployments), some companies disable PST creation entirely via Group Policy. If you don’t see the ‘Add’ button in Data Files, that’s why — and you won’t have any to delete.
Keyboard Shortcuts
| Action | Shortcut | Alt Sequence | Notes |
|---|---|---|---|
| Open Account Settings | Ctrl+Shift+P | Alt+F+A | Works in all desktop versions since 2013 |
| Switch to Data Files tab | — | Alt+D | Once Account Settings window is open |
| Select & remove highlighted file | Enter then Delete | Alt+R | ‘Remove’ button is focused after selecting file |
| Close Outlook fully | Alt+F4 | — | If system tray icon remains, right-click → Exit |
Cheat Sheet
| Step | Where to Find It | Critical Check |
|---|---|---|
| 1. Detach the file | File > Account Settings > Account Settings… > Data Files tab | Confirm ‘Remove’ is enabled — grayed out means it’s your primary mailbox |
| 2. Restart Outlook | Task Manager → Processes tab → end OUTLOOK.EXE | Check system tray — right-click icon → Exit if present |
| 3. Locate the file | Search %USERPROFILE%\Documents\Outlook Files\ or %LOCALAPPDATA%\Microsoft\Outlook\ | Match filename exactly — e.g., Archive_2020.pst, not Archive.pst |
| 4. Delete manually | Right-click → Delete → empty Recycle Bin | Do NOT skip this step — detached files remain on disk and consume space |
| 5. Verify cleanup | Reopen Outlook → Data Files tab → confirm absence | Also check disk usage — 2GB+ PSTs should vanish from folder view |
| 6. Shared mailbox note | File > Account Settings > Email tab → double-click account → More Settings > Advanced | If shared mailboxes disappeared post-deletion, re-add them here — they won’t auto-restore |
| 7. OST-specific fix | Account Settings > Email tab > Change > More Settings > Advanced > Offline Folder File Settings | Click ‘Rebuild’ instead of deleting — avoids 4-hour re-syncs |
