Can´t receive external emails (eg gmail hotmail)

Today, september 6th, 2017 I stop receiving emails from external domains such as gmail, hotmail, or every other domain. We do receive emails from our server (other domains hosted in the same server) The external forwarders didn"t receive any bounce back email or error, the emails didn"t arrive even in the mail queue. So I opened a ticket and I copy for all of you the response at the end of the explanation. I solved the problem by updating the Cpanel, because de Cpanel Versions 64 and previous were having this problem. Once the system updated, the emails arrived at once. The complete message was this: "It appears that Comcast has added new IPv6 ranges as authorized senders for mail. These new IPv6 ranges, in cPanel 64 and earlier, are parsed in such a way that causes Exim to fail when attempting to read the new ranges. This issue only affected cPanel Email -> Greylisting -> Common Mail Providers). This issue is not present on cPanel 66. When a sender encounters this error, Exim sends back a 421 response, prompting the sender to try again later. Most sending servers will automatically attempt to resend any mail that was previously rejected. We have created an internal case with our developers to have this looked into. This case's ID is CPANEL-15672. While not publicly viewable, this case ID will appear in our changelogs if changes are made as a result of this case: Change Logs - Change Logs - cPanel Documentation Our developers have since rolled back the changes to the Common Mail Providers list while they work to correct the issue relating to the parsing of certain IPv6 addresses. That being the case, all you'll need to do to fix this issue is run the following command: == == == == == == == == /scripts/setup_greylist_db --update_common_mail_providers == == == == == == == == "