I am able to receive emails but not send?

In most cases the root cause of not being able to send email entails the following:

1. Incorrect Email Setup Setting

2. ISP is blocking the port you are using to send email.

3. You have blocked yourself from the server by entering information in, too many times.

NOTE: When one of your email users have this issue, it effects all of you. 

QUICK TIPS: Always remove all email from your outbox before attempting to send again. Having email in your outbox when you have an error stops all email. If you are using outlook, move the email to drafts, shut down Outlook, then restart your computer. Outlook caches old setting that even shutting down the program will not allow for a full reset. Shutting the computer off, then back on, will.


We will address each one as follows:

1. Incorrect email setup setting:

Typically this can be solved by verifying your setting. The correct settings are as follows:

incoming mail server (i.e. POP3/IMap) = mail.yourdomain.whatever

outgoing mail server (i.e. SMTP) = mail.yourdomain.whatever

Ports: 

POP3: 110
POP3 SSL:     995
IMAP: 143
IMAP SSL:     993
SMTP: 25
SMTP Alternate: 26
SMTP Alternate: 587
SMTP SSL: 465

If you are having issues sending email, switch SMTP ports to 587. Once you have verified your setting, and they are correct, then move on to the next option, your ISP is blocking you.


2. ISP is blocking the port you are using to send email.

Your internet provider is blocking you from using anyone's outgoing mail servers but their own. Many major ISP's are blocking outgoing emails, specifically on port 25. In some cases they turn this on or off to slow email traffic to their networks. Additionally they do this is to prevent you from using their internet connection for spamming purposes. You will still be able to send emails, but only by using your ISP'S outgoing mail server or by using one of the alternative ports of 587 or 485 on your account. 

Using Your ISP Server

Every ISP's outgoing mail address is different, but for the most part they will be mail.yourispname.com For example, if you had hosting with AOL.com, their outgoing mail server would look like this: mail.aol.com If mail.yourisp.com does not work and you are still unable to send emails, you will need to call your internet service provider to find out what their outgoing mail server is. See our list of ISP smtp servers. In most cases they have given you an email account with your internet service. THe best thing to do is to set that up, on a computer attached to your network. Typically the most frequently used one. By doing this, you show your ISP that you are authorized to use the standard network ports.

Using the HostBlitz Alternative/Secure Ports

By using a different port other than the ones that average programs have access to, you create an authenticated user. No one can send through most servers on port 587 or 465 unless they are authorized. Your ISP knows this and therefore is less stringent on those ports. In most cases they allow the traffic to pass right through. Using 587 is the most common for our clients an allows road warriors the ability to attach to any ISP nationwide and be able to send email through our servers.


3. You have blocked yourself from the server by entering information in, too many times.

In some cases users will forget their user name or password, enter it in two of three times, and block their IP address. Note that if you have 5 people in your office, and they do this more than 5 times in a 12 hour period, it will block every computer on that particular IP address. Use caution. If this happens, visit www.whatismyip.com, copy your IP and email us it at support@hostblitz.com. Our security team will research it within our firewalls and will remove it from the system. If you are on a dedicated IP, we can whitelist your IP so that if you do make that mistake, it won't stop the entire office. 


By making sure you have the correct settings, choosing the correct port, and being mindful of using the correct user name and password, you can avoid ever having the most common email issues.



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