I can’t send emails. Top 3 reasons.

I can't send emails. Top 3 reasons.

Communication in general is a key factor for every business. Without communication sales channels will not work. In 2017 most of the communication is done online and people use email services to communicate quickly and effectively. Everyone today has an email address and use it to contact vendors, customers or friends. The email communication is probably the most important factor for businesses today. I don’t know a single business or a person who do not use email services daily – especially businesses. If the email server is down and a business can’t communicate with their clients they suffer and lose money. ScalaHosting recommends all businesses to use a business email hosting service. The answer is simple – reliability. You can’t have a free email box and expect to receive the best email service or have 24/7 access to technical support. Using one hosting plan for both your web site and email services is not a great idea either if you run a business. It’s best to have your email communication handled by a separate email server dedicated to do that job only. The result is better email services and decreasing the chance for email problems.

I want to share what are the top 4 reasons why lead to email problems nowadays. Those issues actually occur on daily basis for different people all over the world. They are pretty easy to fix and avoid.

Port 25 is blocked by the ISP

That’s the most often cause we see. Many internet service providers block port 25 in their network to avoid compromised computers to send SPAM. In that way the IP ranges of the ISP does not get blocked in blacklists and they don’t have to deal with abuse complaints sent to them from different authorities. Port 25 is used for SMTP communication and you will usually connect on that port to your SMTP server to send emails. Since your ISP blocked it you can’t connect and can’t send emails. ScalaHosting has implemented an easy fix for that. We also keep port 26 open so clients can connect to it too to send emails. You just have to change the SMTP port from 25 to 26 in your email client configuration and then you will be able to send emails again.

503 valid rcpt command must precede data

That’s a common error users get when they didn’t configure their email clients properly. In most of the cases, the email user didn’t enable email authentication in their mail client. As a result they try to send a message from the server without authenticating with a username and a password. ScalaHosting mail servers require authentication to avoid spam from being sent. Once you enable email authentication you will be able to send emails as long as all other settings are configured properly. If you are not sure have a look at how to configure your email in Outlook. Note that your firewall or antivirus system may cause the same error. Try disabling them if you are getting the error even though SMTP authentication is enabled.

Your SMTP IP is blacklisted

If your server was used to send SPAM at some point it might have been blacklisted in an RBL. As a result the servers which use that RBL to filter incoming SPAM will not accept your emails and they will bounce back to you. SPAM is usually sent when a web site or an email address is compromised and the hacker happen to send thousands of emails from the server. That’s hard to happen at ScalaHosting because we monitor all servers mail queues 24/7. We get alerted if someone is sending too many emails in order to check if they are spam related or not. If the user is sending SPAM actions are taken to stop it. As a result our network is clean and our customers can send emails. If your business relies on email communication and it is very important for it then we recommend to use your own server – VPS or a cloud server. It will give you your own IP and it will isolate your business from the shared hosting environment. That will significantly decrease the chance of your IP to be blacklisted.

Write a Comment