mxout02hhb.1und1.net has no MX records.
Question and response
Question
dig mxout02hhb.1und1.net. MX
Answer
The response has no answer records.
Authority
1und1.net. 8640 SOA dnsdb.versatel.de. hostmaster.versatel.de. 2026021202 21600 3600 604800 8640
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0