I set up my Comcast account in my Blackberry. Everytime I open up my email folder all messages are marked as read on my computer. Even if I don't open up a message. My handheld shows what has been open or not by if it's bold or not.
My desktop shows everything as read. How do I fix this?

Are you using the comcast web email interface, or Outlook?

Forgive me...but how would I know??

You would know by what you open on your PC desktop to read your email.