When I reply to an incomming email from from outlook 2007 I get a message from the system administrator indicating the the reply is undeliverable. I can send an email to the account if I create a new message but not if I reply to the message.
The list of recipients is blank and there is no indication as to why it has been undelivered.
Using Outlook 2007, on a Windows XP Professional 2002 SP3, Company network with en Exchange 2003 Server, Smime enabled.
Sorry if this question has been asked before but I just cannot find the answer.