Anybody else having issues sending emails through smtp.isdsl.net server. Getting intermittent error 451, wanted to see if anybody else uses this server and is having problems.
Try not to send mail via port 25. Use 587 or 465 (depending if you have ssl or not). Especially if you have your own domain. ISP's tend to "hijack" port 25 because it's so prone to be used by spambots that it will give you errors or mails being bounced back depending if the recipient server is checking for that or not