Is anyone having this problem of email not deleting? I have .75 OS. I can't delete it off my phone. It's weird. I could delete all my other messages, but it seems I cannot delete this one message from a friend. I have deleted all his other messages but one still remains.

First thing, try a hard reset, i.e. pull the battery for 30 seconds or so.

Also, is it a saved messaged? I think you would be prompted, asking if you want to delete a saved message, but my memory is fuzzy.