checkeremail.com

checkeremail.com is a mail server (MX) used by 1 checked domain. Based on public DNS, it looks healthy.

IP & reverse DNS

IP address	Reverse DNS (PTR)	FCrDNS	DNSBL
52.101.11.19	mail-sa9pr04cu00203.inbound.protection.outlook.com	Yes	Not listed
52.101.8.5	mail-dm2pr02cu00105.inbound.protection.outlook.com	Yes	Not listed
52.101.194.0	mail-ch5pr02cu00200.inbound.protection.outlook.com	Yes	Not listed
52.101.40.26	mail-cy7pr21cu00102.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:f913::1	mail-cy1pr02cu00101.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:c902::4	mail-sj0pr03cu01504.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:f802::	mail-byapr05cu00400.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:c902::5	mail-sj2pr05cu00505.inbound.protection.outlook.com	Yes	Not listed

FCrDNS (forward-confirmed reverse DNS) passes when the IP’s PTR name resolves back to the same IP. It is a key signal that a mail server is legitimately configured; servers without it are widely treated as suspicious.

Server software

Detected software	Microsoft Exchange / 365 (from SMTP banner)
SMTP banner	`220 SJ1PEPF000023CD.mail.protection.outlook.com Microsoft ESMTP MAIL Service ready at Wed, 19 Aug 2026 08:16:54 +0000 [08DEFDB6496072DA]`

Captured passively during an earlier check — we do not actively scan mail servers.

Domains using this mail server

cummingsplumbingtucsonaz.com

What does this mean?

These are public DNS facts about the mail server checkeremail.com — the host that other servers connect to when delivering email for the domains above. We do not actively probe it over SMTP; the checks here are reverse DNS, forward-confirmed rDNS and public blocklists.

To look up a specific domain’s mail setup use the MX Lookup, or verify an address with the email checker. Learn more in email servers explained.