All this is urgent please help. While applying patches tonight I rebooted my exchange 2007 server and now I don't seem to be able to send messages to certain outside domains.
Delivery has failed to these recipients or distribution lists:
User One
Your message wasn't delivered because of security policies. Microsoft Exchange will not try to redeliver this message for you. Please provide the following diagnostic text to your system administrator.
The following organization rejected your message: nlpi136.prodigy.net.
Sent by Microsoft Exchange Server 2007
Diagnostic information for administrators:
Generating server: server-v.domain.com
user@sbcglobal.net
nlpi136.prodigy.net #550 5.7.1 Connections not accepted from servers without a valid sender domain.nlpi136 Fix reverse DNS for 38.104.195.22 ##
ExchangeActive Directory
Last Comment
awender2
8/22/2022 - Mon
suriyaehnop
It is happened to other external domain like yahoo.com or gmail.com?
It like that your try to send an email to distribution list at recipietn site. Could you make sure that it is user or distribution? if distribution, please make sure that you ask the recipint IT department to uncheck the "Request all senders are authenticate"
You may try to reinstall the patches at control panel. Reboot the server then send to " same recipient" and verify if message able to deliver.
Also, pls check at mxtoolbox.com for your domain if it is blacklisted. if yes, then you might have to change your sending server ip. Also, make sure that you have a A record with pointer created for the public ip address which is sending out email .. and it shud be created on a public dns server.
awender2
It seems that the reverse DNS for your ISP STMP sender is not resolved. Many SMTP hosts don't accept connection where reverse DNS fails.
It like that your try to send an email to distribution list at recipietn site. Could you make sure that it is user or distribution? if distribution, please make sure that you ask the recipint IT department to uncheck the "Request all senders are authenticate"
You may try to reinstall the patches at control panel. Reboot the server then send to " same recipient" and verify if message able to deliver.
http://technet.microsoft.com/en-us/library/bb232118(EXCHG.80).aspx