email stuck in deferred queue

[NoDoze]

Emails to payroll-us.com are getting stuck in the deferred queue with an error message of "connection timed out", but they are able to email us....?

In this thread: email in deferred queue
the case was no MX record...

In my case I get:
Retrieving DNS records for payroll-us.com...

DNS servers
ns01.domaincontrol.com [216.69.185.1]
ns02.domaincontrol.com [208.109.255.1]

Answer records
payroll-us.com SOA
server: ns01.domaincontrol.com
email: dns@jomax.net
serial: 2009121000
refresh: 28800
retry: 7200
expire: 604800
minimum ttl: 86400
86400s
payroll-us.com NS ns01.domaincontrol.com 3600s
payroll-us.com A 72.167.183.25 3600s
payroll-us.com NS ns02.domaincontrol.com 3600s
payroll-us.com MX
preference: 10
exchange: server528.appriver.com
1800s
payroll-us.com MX
preference: 20
exchange: server529.appriver.com
18


When I do a lookup of the email server domain, I only get:
Answer records
server528.appriver.com A 174.143.82.76 21600s

I've already whitelisted the domain in salocal.cf.in

Any ideas why the connection would time out?

Thanks!

[uxbod]

telnet server528.appriver.com 25
Trying 174.143.82.76...
Connected to server528.appriver.com.
Escape character is '^]'.
554 Transaction FailedConnection closed by foreign host.

Oops! its the same for server529 aswell.

That was from my workstation yet from the server it is okay ... Would you try a telnet and see if you get a response. You could also try putting through a synthetic transaction.

[NoDoze]

what does that mean?

yea unable to telnet to their email server...so does that mean the issue is they don't have port 25 open...?

[uxbod]

No; they do have port 25 open but what I believe is happening is that they are checking against some sort of database and if a IP(s) exist they are aborting the SMTP connection. I believe payroll-us would need to ask AppRiver why this is happening.