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Hi <br />
Since we changed our I-Provider &nbsp;i have Problems sending mails with my ex2013. i cant send mails. i get the error Remote Server returned '501 Sender domain is invalid. Could not find DNS record.<br />
<br />
Where do i have to check. For Information i use port 587, but i dont have a official ssl certificate.<br />
<br />
Thanks <br />
<br />
Werner
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Hi 
Since we changed our I-Provider  i have Problems sending mails with my ex2013. i cant send mails. i get the error Remote Server returned '501 Sender domain is invalid. Could not find DNS record.

Where do i have to check. For Information i use port 587, but i dont have a official ssl certificate.

Thanks 

Werner

Exchange 2013 send mails error Remote Server returned '501 Sender domain is invalid. Could not find DNS record

Small Business Server (SBS) is a line of server operating systems targeted at small businesses by bundling the operating system with a number of other Microsoft products that would normally need to be purchased or licensed separately. The most notable inclusions are Exchange, SQL Server, SharePoint and ISA/TMG (Microsoft's firewall and proxy server).

Within Internet message handling services (MHS), a message transfer agent or mail transfer agent (MTA) or mail relay is software that transfers electronic mail messages from one computer to another using a client–server application architecture. A MTA implements both the client (sending) and server (receiving) portions of the Simple Mail Transfer Protocol (SMTP). The terms mail server, mail exchanger, and MX host may also refer to a computer performing the MTA function. The Domain Name System (DNS) associates a mail server to a domain with mail exchanger (MX) resource records containing the domain name of a host providing MTA services.

Email Servers

An email client, email reader or more formally mail user agent (MUA) is a computer program used to access and manage a user's email. A web application that provides message management, composition, and reception functions is sometimes also considered an email client, but more commonly referred to as webmail.