IIS and SMTP - SMTP Mail from one Domain Timing out

Author

SMTP Mail from one Domain Timing out

hartnett.mike@gmail.com

2006-03-03, 6:27 pm

A Couple of companies that we regurlarly recieve mail from now route
there mail through a company called messagelabs.
Any mails now been recieved from messagelabs are Timing out.
Using IIS on a Relay PC.
See Logs below
2006-03-03 00:12:35 193.109.255.100 mail24.messagelabs.com SMTPSVC1
RELAY4 192.168.*.* 0 HELO - +mail24.messagelabs.com 250 0 SMTP - - -
2006-03-03 00:12:35 193.109.255.100 mail24.messagelabs.com SMTPSVC1
RELAY4 192.168.*.* 0 MAIL -
+FROM:<61826.172773302@ems.euromoneyplc.com> 250 0 SMTP - - -
2006-03-03 00:12:35 193.109.255.100 mail24.messagelabs.com SMTPSVC1
RELAY4 192.168.*.* 0 RCPT - +TO:<user@mydomain.com.COM> 250 0 SMTP - -
-

Timeout:
2006-03-03 00:35:17 193.109.255.100 mail24.messagelabs.com SMTPSVC1
RELAY4 192.168.*.* 0 TIMEOUT - mail24.messagelabs.com 121 635564 SMTP -
- -
2006-03-03 00:35:17 193.109.255.100 mail24.messagelabs.com SMTPSVC1
RELAY4 192.168.20.*.* 0 QUIT - mail24.messagelabs.com 240 635574 SMTP -
- -

Any Help would be great.

hartnett.mike@gmail.com

2006-03-07, 5:54 pm

Anyone ???

Sanford Whiteman

2006-03-08, 2:49 am

>Any mails now been recieved from messagelabs are Timing out.

Okay, that's pretty precise. If these are the only timeouts in your
logs, start looking at tracerouting to the connecting IPs from your
mailserver, and running a network sniffer to look for errors.

Sorry I can't be more directly helpful, but the actual timeout is
almost certainly happening outside of SMTP, either some weirdness with
the local TCP/IP stack, router MTUs, stuff like that.

You could also temporarily increase the IIS connection timeout and see
if, for some reason, these sessions are inactive fot just over the
timeout threshold.

--Sandy