Difficulty deleting Draft messages from Deleted Items folder in Outlook.

Try this sequence in Outlook.com or Outlook on the web first, since stuck deleted items can sometimes be cleared there even when the desktop app keeps bringing them back:

1. Open the Deleted Items folder and select Empty folder.
2. At the top of the message list, next to Recover items deleted from this folder, select Recover.
3. Then select Empty folder again.

If the items still do not clear:

1. Leave the browser window open for a while after deleting. If many items were previously deleted, Outlook may need time to finish moving or removing them.
2. Try deleting a smaller batch instead of multiple items at once.

Because the stuck items are Draft messages, also check whether they are still present in Drafts:

1. Open Drafts and select the message.
2. Select Delete.
3. Then open Deleted Items and delete the message again from there.

In Outlook Web App, another supported way to permanently clear Deleted Items is:

1. Right-click Deleted Items.
2. Choose Empty folder.
3. Choose OK to confirm permanent deletion.

If only specific items are stuck, in the light version of Outlook the supported method is:

1. Open Deleted Items.
2. Select the check box next to each stuck item.
3. Right-click and select Delete.

If the mailbox is Outlook.com, items in Deleted Items are recoverable for 30 days, so they may remain recoverable even after deletion during that period.

References:

• Cannot empty the Deleted Items folder in Outlook.com | Microsoft Support
• My email message doesn't send | Microsoft Support
• Read and send email in the light version of Outlook | Microsoft Support
• Mail in Outlook Web App | Microsoft Support