PKARP@IU.AI.SRI.COM (Peter Karp) (02/08/88)
As long as we're all airing out pet peeves on internet mail, here's mine. In general I've observed that the error messages most mailers generate are very confusing to users. They are confusing in that after reading error messages, users often still have little clue as to exactly why their mail failed, and thus of how to generate a new address that is likely to succeed. Here's an example. Imagine that fred@host1 sends mail to joe%host2@host3.arpa . It happens that "host3.arpa" has never heard of "host2", thus host3.arpa returns an error reply to the RCPT TO command given to it in its SMTP conversation with host1. Fred receives a rejection message from the mailer at "host1". This message says something like: joe%host2@host3.arpa: 550 unknown host Now, mail wizards that we are, we can all figure out that since this message was generated by the mailer at "host1" and contains an SMTP error code, the problem is in fact that "host3.arpa" never heard of "host2". However, Fred has no clue what's going on. He doesn't know from SMTP connections. He may not be able to figure out which host name is unknown here, and he probably doesn't know what host actually rejected the address. Thus, he forwards the error message to a mail wizard for explanation, which wastes everyone's time. These problems become much, much more tricky when much longer message routes are involved; it's very hard to figure out which host generated an error message and exactly what address it was given that caused it to barf. My suggestion is that Fred should see something that looks like: 550 HOST3.ARPA rejects address "joe%host2@host3.arpa": unknown host "host2" This has the advantages that: a) The host that rejects the address has clearly identified itself b) It tells us what address it was handed that caused it to barf c) It tells us what part of that address was problematic, and why The error messages in my VMS Pony Express mailer are of this form. I suggest that other mailer maintainers modify their error messages in this way. Peter -------