It must be very frustrating to write to a friend and realize your emails aren't getting through. Let's look at why this might happen.
This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: xxxxxxx@xxxxxx.com host xxxxxx [123.2xx.2xx.5] SMTP error from remote mail server after end of data: 550 permanent failure for one or more recipients (xxxxxxx@xxxxxx.com:blocked)
This is a Block. That is, the provider you're writing to (possibly Gmail or Hotmail) doesn't want to deliver your email for some reason.
What to do if you receive this response?
1. Verify your IP is not blocked
Since this is a permanent block, it means the recipient definitely doesn't want your email. This may be because the IP of your email server is on a blacklist.
How do I know if my domain is on a blacklist?
The easiest, fastest and most reliable way is to use this tool:
- https://mxtoolbox.com/blacklists.aspx
- Search by your domain and examine the result
Ideally the result when searching your domain should show all green — meaning your IP is not on any spam list, which is excellent news. But since the provider rejected you, you might see some red results, indicating your IP is blocked by some spam lists.
What do I do if my IP is on a spam list?
The chances of this happening with your site hosted at Bacan are very small, since we use antispam systems on the output of our servers so that any spam leaving our IPs is blocked immediately. But no provider is 100% free from entering these lists.
If your domain is hosted at Bacan, write to us immediately at ayuda@Bacan.com, and we guarantee we'll address the problem with maximum diligence.
What do I do if my domain is always on a blacklist?
That's easy — come to Bacan and you'll notice a definitive difference between your current provider and us.
2. Verify your domain is correctly configured
The first thing to ask yourself is:
Do you have the SPF record correctly configured on your domain?
SPF (Sender Policy Framework) is an ingenious system that allows your domain to tell email recipients to only accept email from a specific source.
That is, if someone writes an email using your domain (to impersonate you) from an IP address other than the authorized one, the email will be rejected.
This means that if your SPF record is misconfigured or doesn't exist, it's easy for legitimate email to be rejected.
It's also true that if you yourself write from an email server (from your internet provider) that is not authorized, it creates the same situation and your emails will be rejected. That's why it's always essential to correctly configure your outgoing mail server.
How do I verify my SPF is properly installed?
You can verify it at:
What do I do if my SPF is not installed?
Both cPanel and DirectAdmin allow you to install an SPF record.
In cPanel:
In DirectAdmin:
Go to DNS management and create a TXT record. Once selected, choose the SPF record.
If after reviewing and correcting these two problems you still have trouble sending email, contact our technicians