Outlook storage folders suddenly disappeared

Question

Years of saved emails stored in folders and subfolders suddenly disappeared yesterday. The "storage folders" folder has nothing in it. Oddly, a second whole section of storage folders, imported from an older machine, remain and have not been deleted. I'm running Windows 10, looking forward to upgrading to 11 soon, and imagined transferring everything, including the stored emails, to a new machine.

Answer 1

Hi @Malcolm MacKenzie

Thank you for reaching out, and I understand how concerning it is to see your saved Outlook folders disappear unexpectedly. I’ll be glad to help you recover the missing folders and ensure your data is safe as you prepare to move to a new device. 

It sounds like the folders were stored in a local Outlook Data File (.ost). If that file is not currently connected to Outlook, the folders won't appear—even though your data is still safe on your PC. 

If you're using the classic Outlook for Windows, here's what we can check together first: 

• Go to File > Account Settings > Account Settings. 
• Click on the Data Files tab. 
• Look for the data file (.ost) that previously held your storage folders 
• If it’s missing, click Add, then browse to C:\Users[UserName]\AppData\Local\Microsoft\Outlook 
• Once added, open the file and your folders should reappear 

If no .ost file is found, or the folders are still missing, it’s possible the file was deleted, moved, or you're using a version of Outlook that doesn’t support local storage (like the new Outlook for Windows). 

To help us guide you better, could you please confirm: 

• Which version of Outlook you're currently using (e.g., Outlook 2016, Microsoft 365, or the new Outlook)? 
• What type of email account you use (POP, IMAP, or Exchange/Microsoft 365)? 
• Have you used any backup tools like File History or other cloud services on your PC that might have saved these files? 

Once we have this information, we’ll be able to guide you through the most effective recovery steps. I’m here to support you every step of the way. 

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