If you use a custom domain with MailSlurp and have periodic failures or 530 error messages from major providers like Yahoo and Gmail the MX records for your domain are likely misconfigured.
Most email receiving issues that occur on MailSlurp are due to misconfigured domain name records.
A 530 failed to deliver error typically means you are using the private
email-smtp.us-west-2.amazonaws.comMX record. This record is not for public use and will fail. Please use only the
10 inbound-smtp.us-west-2.amazonaws.comrecord for your domain and no other MX records.
First check the DNS records on your domain. Using a terminal and
dig you can fetch the records like so:
> dig mailslurp.fyi mx ; <<>> DiG 9.16.1-Ubuntu <<>> mailslurp.fyi mx ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 63450 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 65494 ;; QUESTION SECTION: ;mailslurp.fyi. IN MX ;; ANSWER SECTION: mailslurp.fyi. 600 IN MX 10 inbound-smtp.us-west-2.amazonaws.com. ;; Query time: 35 msec ;; SERVER: 127.0.0.53#53(127.0.0.53) ;; WHEN: Mi Jan 06 18:30:15 CET 2021 ;; MSG SIZE rcvd: 94
You should have one MX record only with the value:
name: your-domain.com. ttl: 600 type: MX (IN) record: 10 inbound-smtp.us-west-2.amazonaws.com.`
Note period at the end of the name and record is required (if your DNS settings allow it) and is valid for DNS server names and records.
If you create inboxes that use a subdomain your account must be manually configured. Please contact support in this case.
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Diagnosing receiving errors with Gmail, Yahoo, etc.
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