Email is stuck in the queue with 421 4.2.2 Connection dropped due to SocketError

Question

We recently installed an Exchange 2010 Server and we are having some problems sending emails to certain domains. Email is stuck in the queue with 421 4.2.2 Connection dropped due to SocketError.

Any Suggestion? The below is the message when using telnet command:

EHLO *******
250-aa6061.com Hello [********]
250-TURN
250-SIZE 15360000
250-ETRN
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-8bitmime
250-BINARYMIME
250-CHUNKING
250-VRFY
250-X-EXPS GSSAPI NTLM LOGIN
250-X-EXPS=LOGIN
250-AUTH GSSAPI NTLM LOGIN
250-AUTH=LOGIN
250-X-LINK2STATE
250-XEXCH50
250 OK
MAIL FROM:*******
250 2.1.0 *********....Sender OK
RCPT TO:[email protected] NOTIFY=success,failure
**550 5.7.1 Your email messages have been blocked by the recipient OR by Trend Mic
ro Email Reputation Service. Contact the recipient or his/her administrator usin
g alternate means to resolve the issue.**

Solution

Did you even read the error message?

Your mail is being blocked by aa6061.com because they deemed you (etla.com.cn) not trustworthy.

It's quite clear what you have to do (it's even noted in the 550 response!):

You have to contact them to know about what the particular issue is. It's either a misconfiguration on their part, or on your part. It seems that they are at fault, since a quick search did not yield any particular issues with your mailserver.

Do note however that your second MX seems to be down.

Comments

[David Corsalini]

what happens when you send using telnet from the exchange server? can you post a transcript?

[e0594cn]

Hi, the remote server drop the connection! How can i resolve this issue? Thanks!

[Sarah C. Corriher]

You can check your e-mail reputation with Trend Micro here: ers.trendmicro.com You may also want to check to make sure that you are not operating an open relay, and use one of the online services to make sure you are not on any RBL's.