smtp server tester

Warning: inverse host lookup failed for 52.98.179.146: Unknown host
Warning: inverse host lookup failed for 52.98.252.98: Unknown host
Warning: inverse host lookup failed for 52.98.252.130: Unknown host
FRA-efz.ms-acdc.office.com [52.98.179.146] 25 (smtp) open
220 FR4P281CA0277.outlook.office365.com Microsoft ESMTP MAIL Service ready at Mon, 22 Jun 2026 18:10:37 +0000 [08DECF6B94D36E82]