Email firewalls help filter incoming emails and remove unwanted spam. They use a specific set of rules created by the email server to determine which emails are useful and which are not. Each email message is analyzed to determine if it should be flagged as spam.
Individuals and organizations use email firewalls to protect their organizations and inboxes from malicious messages. Not all firewalls use the same metrics, but the general idea is to monitor emails and user behavior.
When a user flags your message as spam, this information is noted by the firewall and shared with other servers. This can permanently damage your reputation as an email sender.
How Do Email Firewalls Work?
The process starts when an email comes into a protected network. The firewall will scan the message using the predefined rules to either flag the message as spam or put it through. If a specific IP address has a lot of problematic messages, it can be blacklisted (or delisted) by the firewall.
Because this information is shared by the network to other servers and firewalls, this blacklisting can cause significant problems. Email service providers are careful to take spam complaints seriously to avoid having their entire IP blacklisted. If that happened, they wouldn’t be able to serve customers anymore.
Even clean senders who abide by the rules might get their messages marked as spam. This can impact their ability to get through firewalls and spam filters.
How Do Email Firewalls Affect Deliverability?
If a user marks an email as spam, or the email firewall detects red flags that indicate spam, your message will be put into a separate folder and not hit the user’s inbox. That means the user will generally not see or open your message and your content will have no effect.
If you’re found in violation of the CAN-SPAM Act, you could be sued by your ISP. You can also be fined $11,000 for each address on your email list.
If you want to avoid being reported for spam or falling victim to an email firewall, make sure to avoid common practices associated with unsolicited emails. These include specific keywords such as “free” or “click here”, using all capital letters, and overusing punctuation.
Also, make sure you prune your list regularly so that you only have active, engaged users. This will help you avoid spam reports and problems with email firewalls.