Unable to View Emails

Unable to View Emails

I am unable to view any of my emails (sent or received). I can see the list of email subjects, but when I go to select an email to read, it loads, then the list of subjects goes blank and the email I want to see doesn't show up. I have to click on "email" again to pull the subject list back up.
 
I would really like this to be fixed as soon as possible. I can't keep up with my clients because of this.