As you say, it's generally impossible to know what is causing the mail delivery failures from the contents of the "countdown" messages. Nice way to describe them by the way. :) I would recommend sending a note the postmaster asking him/her for information. I've found that sometimes such notes actually are the first indication the postmaster has that there is a problem. In those cases, they serve a more important purpose than just providing you with an explanation of the mail delivery problems. I generally don't mail postmasters at the regional Bitnet/Internet gateways since they are providing a generic service, and probably don't know anything about most of the machines they are asked to contact via SMTP connections. That is, if aardvard.xyz.edu is a workstation that has been down for a week, the postmaster at the xyz.edu mail gateway is probably going to know what's going on (or can find out). But the postmaster at your regional INTERBIT isn't likely to know more than you've learned from the mail rejection notice already. -jj PS - I also consider the postmaster to be another person that's been bitten by whatever software/hardware problem has caused the delivery failure. So, my notes tend not to be "flames" but rather requests for assistance and/or information. There are exceptions of course, but you'll have to decide for yourself if/when the bounces are caused by unforseeable hardware/software problems or negligence and phrase your responses accordingly.