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
52.101.148.1	mail-dx1p273cu00301.inbound.protection.outlook.com	Yes	Not listed
52.101.148.13	mail-dx2p273cu00205.inbound.protection.outlook.com	Yes	Not listed
52.101.148.3	mail-dx3p273cu00103.inbound.protection.outlook.com	Yes	Not listed
52.101.147.1	mail-au1p273cu00101.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:cc2f::	mail-au1p273cu00100.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:cc30::3	mail-dx2p273cu00203.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:cc30::	mail-dx1p273cu00300.inbound.protection.outlook.com	Yes	Not listed
2a01:111:f403:cc30::1	mail-dx3p273cu00101.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 DX3PEPF0000009C.mail.protection.outlook.com Microsoft ESMTP MAIL Service ready at Mon, 5 Oct 2026 20:07:36 +0000 [08DF22FD56DF920D]`

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

Domains using this mail server

codex71.ae

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.