I just finished installing SBS Server 2008 with exchange 2007, However, i managed to send e-mail to world e.g gmail accounts, yahoo.com etc but the server can't receive e-mails. the following was the error that i got from gmail account:
<br> Technical details of temporary failure:
The recipient server did not accept our requests to connect.
[(0) mail.xxx.xxxco.zm . [xx.xx.x.133]:25: 421 4.3.2 Service not available, closing transmission channel] <br/>
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