How much are your auto-replies and error messages revealing about your organisation or activities? Anyone who administers a large mailing list will be familiar with the varied auto-replies and errors that clutter up their in-boxes. For honest administrators, these are just a waste of time, but they can reveal information of use to less salubrious people. If these examples seem familiar, well, they came from you – the recipients of this mailing list:
I am out of office for attending training from 29/Nov to 30/Nov. For assistance, you may contact my supervisor ????? ???? at 1111-1111 or by email to " @ .edu.hk".I am on leave and out of town between 28-Nov-05 and 2-Dec-05. Should you need assistance on service issue, you may contact Mr. ??, ???? ????? @ 11111111 / 22222222, email: - . @ .com.We know what he’s doing, how long he’ll be away and his supervisor’s name and contact details, great for social engineering. And we get his supervisor’s email address, to sell to spammers.
I have annual leave this afternoon, and back on 1 Dec 05, any urgent matter, please contact with ????? ??? (Tel : 66666666).I will be out of the office until the afternoon of December 2nd and will have limited access to emails. Should you require immediate assistance please contact ????? ??? (+852) 2222 2222, . @ .comA bit better, we don’t know if the alternate contact is a colleague or a boss.
I am currently out of the Office. For urgent matter, please call me at 9111 1111.Hey, everybody: call my mobile!
This is the ??????? program at host ?????.?????.edu.hk. < @ . .edu.hk>: host ????. . .edu.hk[1 .1 .1 .1 ] said: 550 No such recipient (in reply to RCPT TO command)Nothing wrong with getting a bounce because an address no longer exists, except that this address was never on the mailing list. The domain name of the address appears to be an internal server at the organisation – if an error is being sent to an external recipient, surely the external version of the problem address should be shown? Was the list message forwarded to this destination?
Delivery to the following recipients failed. ???????@hk1.???.com.hk ?????@hk1.???.com.hk ??????@hk1.???.com.hk ?????@hk1.???.com.hkAgain, the problem addresses were never on the list, and the name of an internal server is revealed. In this case, the addresses without the “hk1.” were on the list – the staff must have left, corporate downsizing, perhaps? Some organisations hide the names of internal servers for security reasons; do they check whether those servers are leaking the names in the error messages?
Your email has been delivered successfully to its addressee at ????????-????????. Please note that our email domain has now changed to @????????-????????.com. Kindly update your record.I would update the record, if you told me the old address I need to change!
----- The following addresses had permanent fatal errors -----
"|exec /usr/bin/procmail"
(reason: addressee unknown)
(expanded from: )
----- Transcript of session follows -----
550 5.1.1 "|exec /usr/bin/procmail"... User unknownDo you really want to advertise your system mis-configuration?
What should you do about these problems? First, it is only polite to exclude all mailing lists from your auto-reply (please start with this one). Second, how much information is really necessary? Do they need to know what you are doing, or that Fred is your boss? Third, are auto-replies really necessary at all? You could set up addresses related to function that can be accessed by any of the relevant staff so that enquiries no longer need to be redirected, and more personal contacts can be dealt with more personally.
And check your server configuration – it might not be doing what you expect.