Question: how do i permanently delete junk mail?
Answer: Open the Junk E-mail Options dialog box. Outlook 2010 and later versions: On the Home tab on the Ribbon, click Junk, and then click Junk E-mail Options. ... 
On the Options tab, click to clear the Permanently delete suspected junk e-mail instead of moving it to the Junk E-mail folder option.
Click OK.