Using Classic Outlook on Windows for personal email, calendar, and contact management
I understand how frustrating it is when duplicate and unnecessary folders make your mailbox difficult to organize.
Please note that Outlook’s built-in folders, such as Inbox, Drafts, Sent Items, Outbox, and Deleted Items, cannot be deleted because Outlook requires them. However, folders that you created can be reorganized or removed.
I recommend creating a simple folder structure that you want to keep, then moving the emails from duplicate or unnecessary folders into the appropriate folders. Once you have confirmed that a folder is empty, right-click it and select Delete Folder. You can also select the Folder tab and choose Show All Folders A to Z, or drag your custom folders to arrange them more clearly.
If you see duplicate copies of actual default folders, such as two Inbox or Sent Items folders, please check whether they also appear in Outlook on the web before deleting anything, as this may indicate a mailbox-level folder issue.
Please feel free to let me know if you have any further updates, thanks.
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