Please keep the following in mind when you are using our SMTP services:
1. We prefer that you use an SMTP server belonging to your ISP or connection provider. Most cable, DSL, and dialup providers have a server for this purpose, and this is the recommended way to send email when connected to those networks. Please consult your provider for more information about these services. In addition to not being subject to blacklisting or mail sending delays that may occasionally affect our network, you will notice a speed increase when sending mail.
2. If you do not wish to use your provider's SMTP service, then you may use our service. Please note that you will be subject to the regulations put on these servers to ensure fair availability to all customers, and to combat spam and other unsolicited email. These regulations include, but are not limited to:
• you must either authenticate over SMTP or have recently checked your mail from the same host that you attempting to send from
• you may be limited by the maximum size of messages that may pass through our network
• you may be limited by the types of uncompressed attachments that may pass through our network in order to limit the spread of viruses
3. Some connection providers, such as Earthlink and some Cox cable networks, require that you use their SMTP server when connected to their networks. If you are able to retrieve your mail from our network but are not able to connect to our network to send mail, you should verify with your connection provider that they allow outgoing connections from TCP port 25 (i.e. outgoing SMTP connections) to external servers.
4. Please see the information below if you are receiving an error message with regard to our SMTP service.
SMTP Error Messages And Their Meanings
- mail server permanently rejected message, If your message contains an Executable attachment, please package before mailing(zip, tar, gz etc). (#5.3.0)
This is a permanent failure. No matter how many times you try to send this message the mail server will never accept it for delivery. If you have any attachments please very that they are not on the following list of prohibited executable attachments.
ba,chm,exe,hlp,hta,pif,reg,scr,shs,vbe,vbs,wsf,wsh,dbx,eml,mht,wab
- 553 Blocked - This server No longer accepts SMTP Connections. For email clients please use (smtp.yourdomain.com) for sending mail. For more information please see http://webmail.hrnoc.net/info/smtp.html.
You will need to update your incoming and going server settings in your mail client. The settings to be used are pop.yourdomain.com or imap.yourdomain.com for the incoming mail, depending on whether you use POP or IMAP to check your mail. For the outgoing server the correct setting to use smtp.yourdomain.com. If you are are using anything else especially mailbox.yourdomain.com they will no longer work. We also recommend that you enable SMTP AUTH in your mail client for reliable sending of email.
If you are using third party DNS you will also need to modify the MX records for your domain to the correct settings. You can find the correct settings at the address below:
http://webmail.hrnoc.net/mail-settings/index.php
- 451 Listed on SBL:
This is a temporary failure, which means that you should try back later. According to the http://spamhaus.org blacklist, you are attempting to connect from a server that is known to house notorious spammers. Please see the URL mentioned for information on how to be removed from the Spamhaus blacklist, at which time you may try to send again.
- 451 This mail was handled by an open relay - please visit
This is a temporary failure, which means that you should try back later. According to http://ordb.org, you are attempting to send mail that has passed through an open relay, which means that it allows anyone to send mail from anyone, to anyone, with no form of verfification. Please see the URL mentioned to learn how to fix this, and then retry your mail later.
- 451 Bad reverse DNS:
This is a temporary failure indicating that you are attempting to connect from a host that does not have reverse DNS. We require that hosts sending mail through our network have reverse DNS records. Please contact your network administrator or connection provider in order to rectify this situation, as all responsible networks should have reverse DNS records.
You can verify that your DNS is or is not set up properly at the address below:
http://webmail.hrnoc.net/info/smtptest.php
- 553 sorry, your HELO host name has been denied (#5.7.1):
This is a permanent failure. No matter how many times you try to send this message the mail server will never accept it for delivery. The sending mail server is pretending to be one of our email servers, or the sender is using a misconfigured mail server which does advertise a legitimate HELO or EHLO.
- 553 sorry, your envelope recipient has been denied (#5.7.1):
This is a permanent failure. No matter how many times you try to send this message the mail server will never accept it for delivery. Incoming email for this recipient has been denied temporarily.
- 553 sorry, your envelope sender has been denied (#5.7.1):
This is a permanent failure. No matter how many times you try to send this message the mail server will never accept it for delivery. Incoming email from this sender has been denied temporarily.
- 451 This mail was handled by an open relay - please visit
