Dovecot and Postfix Mail Queue Problem

[Mikau]

Good afternoon, first, sorry for my english, but I'm salvadorean... I'm noob in Linux, and I want to solve a problem I have.

I have configured Postfix and Dovecot to manage my mail tasks... However, some emails always remain in Mail Queue (Webmin) of my Postfix Server and never go to their destination. When I see in Webmin te Mail Queue, the detail are:

Host or domain name not found. Name service error for name= tribuddb-com.mail.eo.outlook.com type=AAAA: Host found, try again

Its happen with this domain for example:

tribuddb.com

The problema occurs only with some emails. I hope you can help me! Thanks

[NixSavy]

Hi Mikau,

Its resolving tribuddb.com to IPv6, please make sure below entry should ipv4 as below in configuration file.

inet_protocols = ipv4

Thanks