This software scans and verifies open relay servers, including smtp relays, blind anonymous relays, and public proxy lists. It's popularly used by individuals from abuse.net and sendmail.org to test open relays.
What's more, this tool is known to be used by specialists at leading sites such as abuse.net and sendmail.org to test open relays. It's therefore safe to say that it's a trusted resource.
The site features helpful resources such as an Open Relay Database which provides useful information about open relays. There are also Open Relay Usage Articles, FAQs & How-tos, and tips on Closing Relays and Protecting your Mail Server.
To help combat spam, there are Anti-Spam Tips to keep your email secure. Additionally, the Public SMTP List is updated daily ensuring you always have the latest information.
If you're keen on trying out this tool, you can download the free software. To access further resources, membership to the site costs only $29 per month.
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