Frequently asked questions about Debouncer

What is Debouncer?
What are email blacklists?
Why I must monitor mail server’s IP address and domain name against blacklisting?
How I will know that my server is blacklisted?
Why my server is blacklisted?
How to get delisted?
Do you offer blacklist removal services?
Do you offer blacklist circumvention services?
How do I know that my server was removed from a blacklist?
How do I start monitoring Microsoft SNDS/Hotmail/Outlook blacklist?
What are SNDS spam traps? Why should I monitor them? How to identify the spam traps I am hitting?
Debouncer pricing
What locations do you monitor email servers from?
How do I start?

What is Debouncer?

Debouncer is an email blacklist monitoring service. It constantly checks IP address and domain name of your email server against comprehensive database of DNS based blacklists. Debouncer notifies you if your server was added to email blacklist and provides a link to the page with blacklist removal instructions. Also it performs mail server monitoring, domain name resolution monitoring, IP address reverse DNS monitoring and reverse DNS check.


What are email blacklists?

A DNSBL (DNS-based Blackhole List, Block List, or Blacklist) is list of IP addresses published through the Internet Domain Name Service. DNSBL are most often used to publish the addresses of computers or networks linked to spamming; most mail server software can be configured to reject or flag messages which have been sent from a site listed on one or more such lists. Further info may be found here: Email black list (Wikipedia article)


Why I must monitor mail server’s IP address and domain name against blacklisting?

Your outgoing email messages may be filtered out by email servers that consult the spam blacklist you are included in. Your message may bounce:

554-Rejected because 1.2.3.4 is in a black list at dnsbl.sorbs.net
554 Blocked - see http://www.spamcop.net/bl.shtml?1.2.3.4 (in reply to RCPT TO command)

Administrator of mail server may configure any rejection message, even like this:

550 user unknown

In the worst case your email may be silently deleted or marked as spam and delivered to (lost in) recipient's spam mail folder. If it happens, you even will not know your message was not delivered.

There is no way to know which spam blacklists are consulted by recipient's mail server. This is why it is very important to check as many blacklists as possible. You may stay assured that Debouncer actively maintains and updates its spam blacklist database.


How I will know that my server is blacklisted?

As soon as you submitted you IP address and domain, Debouncer starts active monitoring. Debouncer will send you email alert if any changes (new inclusions or removals) were detected. You may also request daily or weekly status reports.


Why my server is blacklisted?

There is a variety of blacklists, and each one uses its own policies of inclusion and removal. Most often the reason for inclusion is spam email message(s) originated from your server. It is not necessary for the message to be a spam, as it may be erroneously (or intentionally) reported as unsolicited email by a recipient or spam scoring program. Incorrect mail server settings, missing reverse DNS record, dynamic IP address - any of the above may result in blacklisting. Often your IP address may be blocked as member of blacklisted IP addresses block. Debouncer will direct you to the blacklist web server, where you may find information regarding inclusion and removal policy.


How to get delisted?

First you must resolve the original issue - remove malicious software, deactivate spammer hosting account, configure mail server properly etc. Some blacklists will detect the change and remove your IP address from database automatically. In some cases you may be required to apply for delisting using the procedure described on a blacklist maintainer web site. Some blacklists may require payment to expedite delisting or to prevent further inclusions. Debouncer will direct you to proper section of blacklist web site - either to removal instructions or to contact page.


Do you offer spam blacklist removal services?

No, Debouncer does not maintain any spam blacklist and may not remove your address. However, we provide consulting, server troubleshooting and maintenance services. We can help you to eliminate problems that resulted in inclusion of your server into a spam blacklist. Please note that we do not render this service to companies and individuals knowingly sending unsolicited email. For further information please contact us via help desk.


Do you offer blacklist circumvention services?

No, Debouncer does not offer any circumvention services. We strongly advise to resolve the issues that resulted in blacklisting. While many blacklist technologies are pretty controversial, being compliant with whatever the blacklisting policies consider a good practice will improve your outgoing email delivery and secure your mail server.
We do not fight email blacklists. We help to leverage their usefulness by providing the missing link: feedback to postmaster.


How do I know that my server was removed from a blacklist?

You will receive an email alert. Debouncer sends email notifications on both inclusions and removals.


How do I start monitoring SNDS/Hotmail/Outlook blacklist?


What are SNDS spam traps? Why should I monitor them? How to identify the spam traps I am hitting?

Please read Identifying and Removing SNDS Spam Traps by Martin Caine


What locations do you monitor email servers from?

We monitor server uptime from multiple locations. You can chose region to monitor from and number of failures before sending an alert.

American Region

  • Los Angeles, California, USA - 185.197.30.224 / 2a04:bdc7:100:e39a:0:0:0:1
  • New York, New York, USA - 107.191.96.156 / 2604:180:2:33e:1:1:1:15
  • Dallas, Texas, USA - 108.181.220.147 / 2604:6600:2003:8b::a

European Region

  • Amsterdam, Netherlands - 185.45.113.72 / 2a02:e00:fff0:161::a
  • Frankfurt, Germany - 172.105.95.254 / 2a01:7e01:e001:1b3:1:1:1:7
  • London, UK - 185.177.148.100 / 2a02:e00:ffe9:62::a

Asia-Pacific Region

  • Singapore - 185.223.207.30 / 2406:ef80:0002:71c8:0:0:0:1
  • Sydney, Australia - 27.100.36.94 / 2402:9e80:1::1:faea
  • Tokyo, Japan - 139.162.106.244 / 2400:8902::f03c:91ff:fe1c:5e01

Worldwide

  • Los Angeles, California, USA - 185.197.30.224 / 2a04:bdc7:100:e39a:0:0:0:1
  • New York, New York, USA - 107.191.96.156 / 2604:180:2:33e:1:1:1:15
  • Singapore - 185.223.207.30 / 2406:ef80:0002:71c8:0:0:0:1
  • Frankfurt, Germany - 172.105.95.254 / 2a01:7e01:e001:1b3:1:1:1:7


How do I start?

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