Sounds like it could be the number of connections allowed. If your relay, or your Exchange server are maxed out, connection-wise, at a given moment, one or the other may bounce the occasional message.
Just a though, Alex Bailey, Matt wrote: | I am my wits end with a problem I am having with my Exchange setup. | | Environment: 2 Exchange 5.5 SP4 servers on an NT domain. (soon to be | upgraded) | | We are doing the ground work to install spam filtering software and have | installed an SMTP relay server using the SMTP service built in to IIS. This | is a temporary solution until the filtering solution is brought into | production. IMS is setup to forward outgoing email to the SMTP relay. 99% | of the email goes out with no problem. I get around 10 messages a day | bounced back with the following error (or something similar): | | smtp;550 Relaying is prohibited | | The SMTP service is setup only to accept connections from selected IP's from | behind the firewall. It is also configured to forward incoming email to the | exchange server. | | I have sent test messages to the same address that generated the bounced | email only to have it delivered to the recipient. | | The reverse DNS on my domain is working and I haven't found our domain on | any open relay or spam lists. | | I am hoping somebody has seen this before because I cannot pinpoint the | problem. | | Suggestions are appreciated, | | ----------------------------------------- | Matthew Bailey | LAN Engineer | CSK Auto Inc. | 602-631-7486 | ----------------------------------------- | | | | _________________________________________________________________ | List posting FAQ: http://www.swinc.com/resource/exch_faq.htm | Archives: http://www.swynk.com/sitesearch/search.asp | To unsubscribe: mailto:leave-exchange@;ls.swynk.com | Exchange List admin: [EMAIL PROTECTED] _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe: mailto:leave-exchange@;ls.swynk.com Exchange List admin: [EMAIL PROTECTED]
