Hi @Vu Nguyen Hoang Phi ,
According to my research, that folder is undeletable, you can only empty it.
- Under Folders, select Deleted Items.
- At the top of the message list, select Recover items deleted from this folder.
- Select Empty folder.
This way, you can empty the Recoverable Items folder and free up space in your mailbox. If you want to know more about the "Recoverable Items" folder, you can refer to this article.
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