Why my e-mail messages are not delivered?
There are a few typical reasons why e-mail message can not be delivered (even to your own working e-mail address).
| Error | Troubleshooting |
|
• Rejected by server |
Message was rejected by remote SMTP server due to their
antispam settings. Most of large smtp servers do not accept mail from home computers (with dial-up or cable IP addresses). You need to send mail via external SMTP server, it's highly recommended. Please open Settings / Common Settings / SMTP and add SMTP server of your Internet Service Provider (ISP) or hosting service. |
|
• Transaction failed |
It usually happens if you try to send mail via an external SMTP
server, but do not provide the correct username / password when
it's required. Please open Settings /
Common Settings / SMTP, double click at the server name and change
Authentication type. The most popular
type is ESMTP. CRAM and DIGEST are used at
the less number of servers, POP before
SMTP is too old, not recommended to use. Note for hotmail.com — please check HELO value. It's very important for them. Open Settings / Common Settings / Mailer and check value of HELO there. It must be the same as at www.massmailsoftware.com/ip. |
|
• Remote server not answer |
Atomic Mail Sender can not access the Internet or your Internet
Service Provider (ISP) does not allow direct email delivery. 1. Please check your firewall and antivirus settings. These programs may block other applications to access network (ZoneAlarm, Panda, AVP, McAfee, Norton, Symantec Internet Security). 2. Make sure your ISP allows direct email delivery. If not, you need to send all mail via ISP STMP server. Please open Settings / Common Settings / SMTP and add SMTP server of your ISP, hosting provider or another SMTP server you have access to (you can find a list of SMTP servers of popular providers here and if you need a commercial SMTP server, check some available options here). 3. If DNS problem, try use Custom DNS (change it in Common Settings / DNS). Try enter public worldwide DNS server — 208.67.220.220 |
|
• SMTP syntax error |
It usually happens if you send username / password when it's not required. Please open Settings / Common Settings / SMTP, double click at the server name and change Authentication to Not required. |
|
• Authentication failure |
You have an error in username or password used to access
external SMTP server. Please open Settings / Common Settings / SMTP, then double click at the server name in the list and correct username and password there. Note 1: Make sure CAPS LOCK is not pressed — it's important! Note 2: Some smtp servers require username "user@mail.com" instead of "user", please investigate. |
|
• Mailbox is full |
Mailbox of the recipient is full. Not all people use Gmail, some have very small mailboxes. |
| • Error 421 | It's a temporary e-mail delivery failure. Usually happens if too many connection from you to the smtp servers. Please decrease Threads Count in Common Settings, or Speed Limit. |
| • Delivering... forever | If you see Delivering... for a
long time (say more then a minute), you need to check the
following: 1. Your message is really large and Atomic Mail Sender need much time to deliver it. Or the outgoing mail scanner blocked it. Check your antivirus. 2. Atomic Mail Sender is completely blocked by your antivirus or firewall and can not access Internet. Please check the settings of these programs. |
If you still have any problems with delivering e-mail, please contact Customer Support. When you contact us, please prepare SMTP connection report. You may get it with double click at the error message. It usually looks like this:
Please copy the text from this window and add to your support query. It is strongly recommended to have logs every time.
See also:
- Email is sent, but not received or delivered to Spam/Junk folder
- SMTP error codes (on site)
- SMTP servers list (on site)


