I'm stumped. As a Comcast Zimbra mail user I don't know my version or where the program resides. I am on a Win XP Pro version 2002 SP3 platform. In Firefox 3.5.3 and IE 7.0.5730.13 there are times when I am unable to reply to an email I have opened from my Inbox.

The problem is machine specific. It is sporadic. All I get is a blue screen and a toolbar line that says, Done. Normally, the blue screen flashes and then the reply form shows. I welcome any and all suggestions.