It happened to me, too. Back in 1995 I was in charge of the Sparc server that handled email. I got a call telling me the we couldn't send mails outside Spain. B

It happened to me, too. Back in 1995 I was in charge of the Sparc server that handled email. I got a call telling me the we couldn't send mails outside Spain. Back then, we had a slow internet connection (128K if I remember well) and sometimes the academic network had issues speaking with the outside world. Two days later we had more complaints. This time it couldn't be a network issue. We had the same problem: one OS upgrade made sendmail use a default config, not ours. Fortunately mail didn't bounce, and after the fix the server was above 20 load average for two days. Good news was no spam came that week.