Outlook classic has lost all files and will not send receive after auto update

Move Outlook’s active .pst data file out of OneDrive and reconnect Classic Outlook to the local copy before attempting repairs or deleting anything.

1. Preserve and relocate the Outlook data file

Do not delete the OneDrive copy yet.

1. Close Outlook.
2. Wait for OneDrive to finish syncing, then quit OneDrive from its system-tray icon.
3. In File Explorer, check: C:\Users\<your-name>\OneDrive\Documents\Outlook Files
4. Copy every .pst file to a folder outside OneDrive, for example: C:\My Outlook Files
5. Rename the copied file so it is clearly distinguishable, such as Outlook-local-copy.pst.
6. Restart Outlook.
7. Select File → Account Settings → Account Settings.
8. On the Email tab, select the affected account and choose Change Folder.
9. Select New Outlook Data File, browse to the copied .pst, and select it.
10. On the Data Files tab, select the entry whose path contains OneDrive and choose Remove.

“Remove” disconnects the file from Outlook; it does not erase its email. A default data file cannot be removed until another file is set as the default. Microsoft documents the complete procedure here: ^1^

If Change Folder is unavailable, the selected account does not use a .pst. Proceed to the profile step below instead.

2. Reopen missing folders

After connecting the local file:

1. Select File → Open & Export → Open Outlook Data File.
2. Select the local .pst.
3. Look at the bottom of Outlook’s folder pane for the newly opened data file.
4. Expand it and check whether the missing mail and folders are present.

For POP accounts, messages, calendar entries, contacts, and tasks can all be held in the .pst; common Windows 10 and 11 locations include C:\Users\<username>\Documents\Outlook Files. ^2^

3. If the PST will not open or folders remain missing

Run the Inbox Repair Tool only against the local copy, retaining the untouched OneDrive copy as a backup:

1. Close Outlook.
2. Search Windows for SCANPST.EXE. A common Microsoft 365 location is: C:\Program Files\Microsoft Office\root\Office16
3. Open SCANPST.EXE.
4. Browse to the local .pst, select Start, and allow it to create a backup.
5. Run the repair; more than one pass may be required.
6. Reopen Outlook and press Ctrl+6.
7. Check Recovered Personal Folders and Lost and Found.

The repair tool cannot recover every permanently deleted or severely damaged item. ^3^

4. Restore sending and receiving

If the local PST opens but Outlook still cannot send or receive, create a fresh profile rather than continuing to alter the existing one:

1. Close Outlook.
2. Hold Shift while starting Outlook.
3. Select Options → New.
4. Name the profile and add the email account.
5. Test sending and receiving before attaching any archive PSTs.
6. If successful, open the recovered local PST through File → Open & Export → Open Outlook Data File.

A profile contains Outlook’s accounts, data-file associations, and message-storage settings, so rebuilding it corrects stale references to the former OneDrive path. ^4^

If the new profile also fails, run Microsoft’s Classic Outlook troubleshooters for connectivity, authentication, and profile setup. These troubleshooters apply to Classic Outlook, not New Outlook. ^5^

Use the provider’s webmail while recovering Outlook. If webmail sends and receives successfully, the mailbox service is operating and the remaining issue is local to Outlook or its configuration.

References

1. How to remove an Outlook .pst data file from OneDrive
2. Find and transfer Outlook data files from one computer to another | Microsoft Support
3. How to repair your Outlook personal folder file (.pst)
4. Create a profile in classic Outlook for Windows
5. Issues sending and receiving email | Microsoft Support