Messages with large attachments seem to get "blocked"

[mandrake]

We are experencing an issue where mails with large attachments never arrive.

Other sites set up similarly (untangle in front of exchange) receive the message, even if a user on the troubled site is in the CC list. An ok site will receive the message, the "bad" site won't.

Strangely enough a users from the "OK" site can then forward the message to the "bad" site.

Exchange SMTP transscript is below (names etc changed to protect the guilty).

Could the untangle spam blocker be preventing the message data from being sent through or should I look elsewhere?


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220 home.com Microsoft ESMTP MAIL Service ready at Tue, 1 Sep 2009 12:29:10 +1000"
EHLO mail.from.com.ac
250-home.com Hello [99.99.99.99]
250-SIZE 10485760
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-STARTTLS
250-AUTH
250-8BITMIME
250-BINARYMIME
250 CHUNKING
MAIL FROM:<from.from@from.com.ac> SIZE=7402873
XXXXXXXXXXXXXXXX;2009-09-01T02:29:10.515Z;1,receiving message
250 2.1.0 Sender OK
RCPT TO:<to.to@to.com>
250 2.1.5 Recipient OK

sixty seconds elapse with no input

451 4.7.0 Timeout waiting for client input

[amlife]

I'm having the same problem . .could somebody help us !!!

[dmorris]

mandrake are you running two virus blockers?

try increasing the timeout on your server from 60 seconds to 90 or 120 seconds.