RU mailserver blacklisted, for Science too

Yesterday the RU outgoing mailserver smtpout3.ru.nl got listed on the SORBS blacklist of confirmed senders of spam and phishing mails. The reason probably is that recently many students fell for phishing mails, which made their username and password known to Internet criminals. These criminals use that to send spam and phishing mails. Because also the Science mailservers use that blacklist, we did not accept mail from the RU mailserver anymore. The senders received an error message: “Your message wasn’t delivered due to a permission or security issue.” We solved this for our Science users by putting the RU mailserver on our own whitelist.