Windows Live Mail – Clear the Junk box all moves to the Inbox

I have a customer using Live Mail.  When he clears or deletes all the emails in his Junk folder all of those emails start populating his inbox.  Not seen this before and haven't seen any articles or answers.  Help appreciated.  I watched him delete all emails form Junk and that just started showing up in Inbox.  In this case there were several thousand.

thanks,

eric