I am not a mail server admin by profession, I took over the responsibilities of the previous person when they left and haven't had may issues until today.
We seem to have gotten a large number of spam email being sent today and now all valid outgoing external mail is stuck as 'Deferred'. We manage one email server for our clients and no email to any external email addresses is getting sent.
Most say 'Delivery Temporarily Suspended'. I have been looking all day for a fix and haven't found one. Any suggestions or help?