ok, click on private messages, when your in your pm folder scroll down and on the right side where it says "messages: 5" (just using 5 as an example) theres a box you can check off, click on the box and then you'll see all your pm's have a check mark next to them, keep scrolling down and at the bottom of pm box theres a thing that says "selected messages:"...click the down arrow near the selected messages and theres an option for delete, click on delete and then click "go" and it will delete them, any questions reply back or PM me.