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Customer Story

MailChannels Transparent Filtering eliminates blacklisting problems for Wowrack

With Founder and Owner of Wowrack, Erward Osckar
In Business Since
Data Centers
Using MailChannels Since


Wowrack, based in Seattle, Washington was founded in 2001 by Erward Oskcar and Jimmy Pandra. Like many startups, Wowrack started out as a small business that ran out of the residence of the owners and has now evolved into owning and operating their own world-class 18,000 sq. ft. data center along with POP’s throughout the globe.

Wowrack currently offers various Hosting services including Private Cloud Hosting, Hybrid cloud infrastructure, Backup and Disaster Recovery Solutions, Dedicated Server Solutions, Colocation, Virtual Private Servers and Bandwidth Delivery.


Wowrack had a problem with compromised user accounts sending spam to Internet destinations via their hosting network. This was causing their IP addresses to be blocklisted on spam blocking lists, preventing their mail servers from delivering legitimate customer emails.

The web hosting company’s IT team worked hard to fight spammers but the anti-spam solution they used was not designed to protect dedicated and cloud servers.

“Our SpamExperts solution was unable to filter traffic in a transparent way, so the mail forwarder IP addresses would often get blocked by real-time blocklists. Once that happens, customers can’t send email out,” says Erward Osckar, the founder and owner of Wowrack.

Wowrack had two main requirements for a new outbound anti-spam solution: it had to be accomplished from the network level, meaning without server configuration and traffic routing only from the switch/router; and it had to be transparent, meaning the IP of the spam filter is not seen in any part—neither header nor connection origin.

Erward says Wowrack chose Transparent Filtering based on recommendations from another user.

The MailChannels Effect

Hosting environments like Wowrack need to secure customer mail servers that they don’t control directly. Transparent Filtering helps achieve this so the network can remain blocklist-free.

Transparent Filtering works in conjunction with Wowrack’s routers to redirect outgoing port 25 traffic from the network to the MailChannels server. Here, SMTP connections are analyzed and spam is removed before mail is forwarded to the intended destination—without modifying the source IP address. The mail appears to be coming from each individual VPS or dedicated server, and Wowrack’s customers don’t know that their mail is being filtered.

“We rely on Transparent Filtering to find out which accounts are sending spam so we can cancel those accounts before they damage our IP reputation,” says Erward. “Since we started using the solution we’ve seen a sharp decline in blocklisting — upwards of 90 percent — on our IP subnets protected by the software.”

Transparent Filtering monitors Wowrack’s outbound mail traffic and once a compromised account is detected, an automatic alert is sent to IT staff. The program then checks different algorithms to make sure it’s a spammer. If a spammer is detected, the compromised account is automatically canceled.

Wowrack is able to create custom policies in the MailChannels web console to monitor each customer account for suspicious activity. Alerts are sent the moment a user, script or server starts spamming.

“We really value the fact that MailChannels notifies us immediately when a customer uses our network for mass mailing, which we don’t allow,” says Osckar. “The notification lets us blocklist that IP and terminate the customer’s account.

We give them three days to move their data before we shut off the server, but with MailChannels blocking their traffic, they can’t send emails during that period so our reputation remains protected.”

With Transparent Filtering, Wowrack has seen its number of support tickets related to blocklisting reduced by more than 90 percent. It’s also reduced the amount of time staff devotes to tracking down compromised accounts and getting de-listed.

“We have a few people dedicated to working on network abuse tickets—it’s particularly stressful to manage this and prone to manual errors,” says Erward. “MailChannels helps us spend less time working on abuse tickets because we’re able to automate outbound spam filtering. Being proactive decreases our chance of being blocklisted.”

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“Since we started using the solution we’ve seen a sharp decline in blocklisting— upwards of 90 percent—on our IP subnets protected by the software.”
Erward Osckar
Erward Oskcar
Founder and Owner, Wowrack




Seattle, Washington


Web hosting

Using MailChannels since


MailChannels product used

MailChannels Transparent Filtering