Unsent Messages

[weathers]

This list of unsent messages is getting longer?  What cause this and what should I do about it?


Attention: You have items in the outgoing queue. Some mailings may be in progress.
 
Type
  Subject
  Messages Left
 
 
Dailymail
  N/A
 
  2
 Resume | Cancel
 
Dailymail
  N/A
 
  4
 Resume | Cancel
 
Dailymail
  N/A
 
  4
 Resume | Cancel

[DW]

It looks like there could be an SMTP error.  How many messages / followups are sent each day, do you figure?  When you hit Resume are there problems?  Do the messages get delivered?