need help with sendmail 553 error
> ----- The following addresses had permanent fatal errors -----
> name@isp.net
> (reason: 553 ns1.domain.com does not exist)
>
> ----- Transcript of session follows -----
> ... while talking to mail.isp.net.:
> >>> MAIL From:<apache@ns1.domain.com> SIZE=909
> <<< 553 ns1.domain.com does not exist
> 501 5.6.0 name@isp.net... Data format error
This only happens when sending to addresses of a few select ISPs. It seems that these particular ISPs do a more thorough check of the sending mailer. Most other destinations work fine.
I imagine that this is a setup issue with sendmail. Does anyone have an idea of what's going on and how I can fix this? I've got a Redhat 7.1 box and I usually use Webmin for administration stuff.
Thanks.
