Outlook problem

[RAFWriter]

Hello. My computer is running Windows XP and Outlook 2003. I have been using
Outlook to access my ATT Worldnet e-mail (which I access via high speed
Internet service separate from ATT, not dial-up) for years with no problem.
All of a sudden, the other day, I am able to receive my ATT e-mail in
Outlook, but not send it. I get the following error message when I try to
send mail:

Task 'AT&T Worldnet E-Mail - Sending' reported error (0x800CCC78) : 'Unable
to send the message. Please verify the e-mail address in your account
properties. The server responded: 450 There is a problem with your reverse
DNS lookup. You must have a valid reverse DNS entry to relay mail through
this server. Please correct the error or contact your internet provider for
assistance before trying again.'

I have gone into my e-mail account settings several times to ensure that my
port information and outgoing and incoming servers are set according to ATT's
requirements. (Microsoft also includes instructions for using Outlook with
ATT Worldnet e-mail, and all the requirements of those instructions as to
port and servers jive with ATT's and are all set correctly). Can anyone
please give me any advice as to how to get Outlook to send my outgoing e-mail
again? Thanks.

 

[Tom Beasley REMAX Realtor]

Hello. My computer is running Windows XP and Outlook 2003. I have been using
Outlook to access my ATT Worldnet e-mail (which I access via high speed
Internet service separate from ATT, not dial-up) for years with no problem.
All of a sudden, the other day, I am able to receive my ATT e-mail in
Outlook, but not send it. I get the following error message when I try to
send mail:

Task 'AT&T Worldnet E-Mail - Sending' reported error (0x800CCC78) : 'Unable
to send the message. Please verify the e-mail address in your account
properties.  The server responded: 450 There is a problem with your reverse
DNS lookup.  You must have a valid reverse DNS entry to relay mail through
this server.  Please correct the error or contact your internet provider for
assistance before trying again.'

I have gone into my e-mail account settings several times to ensure that my
port information and outgoing and incoming servers are set according to ATT's
requirements. (Microsoft also includes instructions for using Outlook with
ATT Worldnet e-mail, and all the requirements of those instructions as to
port and servers jive with ATT's and are all set correctly). Can anyone
please give me any advice as to how to get Outlook to send my outgoing e-mail
again? Thanks.

 

[Brian Tillman [MVP - Outlook]]

Hello. My computer is running Windows XP and Outlook 2003. I have been using
Outlook to access my ATT Worldnet e-mail (which I access via high speed
Internet service separate from ATT, not dial-up) for years with no problem.
All of a sudden, the other day, I am able to receive my ATT e-mail in
Outlook, but not send it. I get the following error message when I try to
send mail:

Task 'AT&T Worldnet E-Mail - Sending' reported error (0x800CCC78) : 'Unable
to send the message. Please verify the e-mail address in your account
properties. The server responded: 450 There is a problem with your reverse
DNS lookup. You must have a valid reverse DNS entry to relay mail through
this server. Please correct the error or contact your internet provider for
assistance before trying again.'

Do you authenticate to the outgoing server? Have you spoken with the people
who administer your outgoing server?