553 validating sender
Subject: Email Solution Sent: 12/12/2012 AM The following recipient(s) cannot be reached: '[email protected]' on 12/12/2012 AM 550 5.1.1 Looking in the Message Options of the bounce back email shows no data in the Internet Header field.My client's IT guy says we're not being blocked, but I cant think of any other reason the bounce would occur.Among all SMTP reply messages, error 550 is surely the most common.It generally comes with a side-message like "550 Requested action not taken: mailbox unavailable" or "550 5 2 1 mail from refused spam site".The fix for me was to comment out "default_transport = error" in /etc/postfix/and then to restart postfix.
Would you like to answer one of these unanswered questions instead?I got the same error message when I try sending it to people with [email protected] Thanks a bunch for all the helps, Tara OK so here's what I have thus far -- and it's not much. They also maintain your MX records for mail, thus all mail incoming or outgoing must pass through them, or relay. Here's something to check; What mail program do you use? ) In that program, open your accounts section and tell me what outgoing and incoming mail server you connect to. You guys run a mail server for your employees, but you don't have mail services so you relay that mail out to Verio which in-turn takes it and processes the data. One thing i don't understand is that it just happen intermittently and to different users at different time. Since they are consultants, its very hard to reach them and we have to schedule time with them to come down all the time. i have the exactly the same problem with you just now. our client should has their DNS configration resetting by adding a MX with the ip which is actaully used to send e-mail. I am very impress with Daemonguy understanding of the above problem. I tried to send a email to a user of other domain but was return a NDR.Here's what I got on your MX record; Server: tao.shinobi Address: 192.168.43.1 Non-authoritative answer: preference = 50, mail exchanger = Authoritative answers can be found from: nameserver = ns11b.nameserver = ns11a.ns11b.internet address = 1.98 ns11a.internet address = 1.38 Not surprisingly, it's the same two IP's for web etc. They may however, leave your headers in place, which when someone does a reverse check will not show up, since you do not run mail services, just a server. Basically your mail server may be acting like a mailman, taking your mail, and delivering it to the Post Office (Verio) as you live in a rural area without standard mailing addresses -- odd analogy I know, but go with me. one of our canadian client can not send their e-mail to us. another way is to use the same exchange server to the DNS to send their e-amil. It stated "There was a SMTP communication problem with the recipient's email server.Of course the best practice here is not simply to erase the address that provokes a 550 error code, but to replace it with a new one whenever possible. If you have another way to contact your user - a phone number, Twitter, Skype...- just send him a line to apprise him that his current email account is wrong, and to ask him a functioning one.