I got resolution for the files not being able to be deleted from the DRAFTS folder. I have a one-year Microsoft Assure plan so I just talked with Microsoft support on this issue. I had already looked and/or tried different "fixes" for this Outlook 2013 IMAP DRAFTS folder issue from internet search results (included the "fixes" post on this site) but without success.
My situation is that I just moved from Windows Vista/Outlook2007 to Windows 8.1/Outlook2013. I started having files remain in the DRAFTS folder after after sending the email for which the file was a draft. I had the same problem if I moved the draft to other folders or even after trying to delete the draft out right. In each case, copies would show up in the DELETED or other folders but the original would remain in the DRAFTS folder. I did not have this issue when I was using Windows Vista and Outlook 2007.
I was a little skeptical that the Microsoft fix would work and concerned that I might lose some email in the process. However, it did work just fine and my email files are fine.
The answer from Microsoft for my particular issue that I mentioned above was to:
- Open "Account Settings"
- Highlight the IMAP account you're having problems with
- Choose "Change" on that menu (opens the "Change Account" window). Everything on this screen should be okay
- Click on "More settings..." (it opens the "Internet Email Settings" window)
- Go to the the "Advanced" tab
- Go to the "Folders" section of the window
- In the field following "Root folder path"...type in the word "inbox"
- Choose "OK" (closes the "Internet Email Settings" window)
- Click "Next" in the "Change Account" window (opens the "Test Account Settings" window and run a test)
- Close the the "Test Account Settings" window
- Click "Finish"
- Close the "Account Settings" window
- Close and reopen Outlook.
I suggest closing Outlook in step 13 because in our first test to see if it worked the files in the DRAFTS folder did not immediately go away (even accounting for the IMAP standard sync delay) and also after pressing "Send/Receive" email. So, we closed Outlook, reopened it, and the DRAFTS folder was empthy. I then did a few more tests saving drafts, sending email from drafts and deleting drafts and the tests all worked fine. My DRAFTS folder was empty when it was supposed to be and had contents when it should. As an additional note, I have subsequently save some emails to DRAFTS and so far they are persisting in DRAFTS until I reopen and send them or or until I specifically delete them from DRAFTS.