What causes your emails to bounce back?

Before you come up with a proper solution to your email deliverability problem, you need to know what causes them in the first place and how your deliverability is actually controlled. In reality, there are 7 primary filters through which your email needs to pass through. These filters are used by ISPs and corporate system administrators as they spam trap as many junk emails as possible hitting their server.

These 7 filters are:

1. Public Blacklists: There are a number of organizations like MAPS and Spam Cop that maintains lists of IP addresses that are linked to known or suspected spammers. These organizations make spammers public for ISPs and others to use them in screening out spam.

2. Private Blacklists: There are many ISPs and corporate system administrators that also maintain their own list of IPs for suspected spammers. There are different criteria based on which these spammers are suspected, such as,

• Complaints received from various subscribers

• Unknown user rates

• Server configuration issues

3. Fingerprinting/Spam Traps: Bright mail is considered to be the most commonly known fingerprinting/spam trap system. They filter known spam messages after they are matched against those that have generated previous complaints, or have delivered spam trap addresses. The “From” address is also considered.

4. Machine Learning-based Content Filters: As the name suggests, these filters are based on the words and phrases present in the email. This can be the content present in the body or the header.

5. Server Configuration: These filters instantly block the emails based on the server configurations.

6. Volume Cap: Some ISPs block your mails if the frequency or the number of connections is too high and exceed the threshold. Be careful so that you don’t surpass your limit.

7. Challenge Response: Some systems require a reply from your end to a challenge message. This usually proves you to be a real person. Such a filter basically confirms your email and domain and sends it to the “allowed sender” list.

B2Bdatapartners’ smart hard bounce management tool removes all bounce messages. It eases your burden of correcting the invalid addresses. Our proprietary hard bounce management tool can scrub your existing customer database by verifying it against our in-house master data file.

For more information:

Visit: http://www.b2bdatapartners.com/

Email: info@b2bdatapartners.com

Call: 800-382-4081

Types of Hard and Soft Bounces

In the last post, we told you what hard and soft bounces are, this post will help you know their different types.

General Bounce (GB)	If the bounce message is unclear and the email server is not able to deliver the email message, it is treated as soft bounces. Example: "Subject: Undeliverable mail"
General Soft Bounce - (SB)	Email is not delivered to the recipient email address temporarily by the email server. Example: "Connection timed out."
Soft Bounce - Dns Failure (SBDF)	Email is not delivered to the recipient email address due to a DNS problem. Example: "Host is unreachable"
Soft Bounce - Mailbox Full (SBMF)	Email is not delivered to the recipient email address as the recipient's email box is full. Example: "Mailbox over quota"
Soft Bounce - Message Size Too Large (SBMS)	Email is not delivered to the recipient email address because the message size is too large. Example: "Exceeded maximum inbound message size"
Transient Bounce (TB)	Email is not delivered to the recipient email address temporarily, but it is still trying. Example: "Warning: message still undelivered after 4 hours. We will keep trying until message is 2 days old"
Mail Block - Attachment Detected (MBAD)	In this case, the recipient's email server is blocking your email due to an attachment. Example: "552 Disapproved attachment"
Mail Block - Relay Denied (MBRD)	This message indicates that the recipient's email server is blocking the email send by the sender’s email server. Example: "551 relaying denied"
Non Bounce (NB)	This clarifies that the message could be a reply from the recipient and was not a bounce, or maybe an unknown bounce format.
Mail Block - General (MB)	This message indicates that the recipient's email server is blocking the email send by the sender’s email server. Example: "550 Message REFUSED by peer"
Mail Block - Known Spammer (MBKS)	Indicates that the recipient's email server believes you are a spammer and is therefore blocking your email. Example: "REJECT Known SPAM source"
Mail Block - Spam Detected (MBSD)	Indicates that for the recipient's email server the message content appears like spam and is therefore blocking your email. Example: "550 Possible spam detected"

B2Bdatapartners’ bounce management tool helps you get rid of all the hard and soft bounces and cleanse your customer database.