Whitelisting ConfTool’s domains and IP addresses

We found out that our organization’s e-mail client is equipped with a spam filter that responds to keywords which are used in ConfTool’s automatic messages, e.g. when users register. Therefore these e-mails are not delivered. How can we make sure that all ConfTool e-mails will pass the spam filter?

First of all, please make sure that the spam filter really is to blame, as other issues might cause the problem.
Please see the related topic "Undelivered Mail Errors: Why wasn’t my e-mail delivered?” for more information.

In order for the automatic e-mails to be delivered and pass the spam filter, please ask your organization’s postmaster to whitelist our domains and/or IP addresses:

conftool.net   -   116.202.134.118  (was: 88.99.71.145)
conftool.com  -   116.202.134.119  (was: 144.76.152.56)
conftool.pro   -   116.202.134.123  (was: 136.243.24.47)
conftool.org   -   168.119.69.19
conftool.de     -  162.55.26.142      (was: 144.76.156.74, 23.88.73.227)

Safety is our main concern and therefore we would like to point out that we exclusively use the IP address listed here and that we never send any unsolicited mails.