https://community.checkpoint.com/t5/Email-and-Collaboration/Skip-listing/m-p/258486#M676 <P>&nbsp;</P><P>I can't find this mentioned in the docs - should <A href="https://learn.microsoft.com/en-gb/Exchange/mail-flow-best-practices/use-connectors-to-configure-mail-flow/enhanced-filtering-for-connectors" target="_blank" rel="noopener">Enhanced Filtering for Connectors</A> be enabled for the HEC connectors in Exchange Online?&nbsp;</P><P>On the receiving end we always see SPF fail when the last external IP is Check Point:</P><LI-CODE lang="c">spf=softfail (sender IP is 52.212.19.177) smtp.mailfrom=dell.com; dkim=fail (signature did not verify) header.d=dell.com;dmarc=fail action=oreject header.from=dell.com;compauth=none reason=452</LI-CODE><P>&nbsp;</P><P>... which I assume is to be expected as we do not have skip listing enabled at&nbsp;<A href="https://security.microsoft.com/skiplisting:" target="_blank" rel="noopener">https://security.microsoft.com/skiplisting</A>?</P> Mon, 29 Sep 2025 18:35:12 GMT ToffenDask 2025-09-29T18:35:12Z https://community.checkpoint.com/t5/Email-and-Collaboration/Skip-listing/m-p/258486#M676 <P>&nbsp;</P><P>I can't find this mentioned in the docs - should <A href="https://learn.microsoft.com/en-gb/Exchange/mail-flow-best-practices/use-connectors-to-configure-mail-flow/enhanced-filtering-for-connectors" target="_blank" rel="noopener">Enhanced Filtering for Connectors</A> be enabled for the HEC connectors in Exchange Online?&nbsp;</P><P>On the receiving end we always see SPF fail when the last external IP is Check Point:</P><LI-CODE lang="c">spf=softfail (sender IP is 52.212.19.177) smtp.mailfrom=dell.com; dkim=fail (signature did not verify) header.d=dell.com;dmarc=fail action=oreject header.from=dell.com;compauth=none reason=452</LI-CODE><P>&nbsp;</P><P>... which I assume is to be expected as we do not have skip listing enabled at&nbsp;<A href="https://security.microsoft.com/skiplisting:" target="_blank" rel="noopener">https://security.microsoft.com/skiplisting</A>?</P> Mon, 29 Sep 2025 18:35:12 GMT https://community.checkpoint.com/t5/Email-and-Collaboration/Skip-listing/m-p/258486#M676 ToffenDask 2025-09-29T18:35:12Z https://community.checkpoint.com/t5/Email-and-Collaboration/Skip-listing/m-p/258628#M677 <P>Might be worth check this with TAC.</P> <P>Andy</P> Wed, 01 Oct 2025 01:51:07 GMT https://community.checkpoint.com/t5/Email-and-Collaboration/Skip-listing/m-p/258628#M677 the_rock 2025-10-01T01:51:07Z