| Event Id | 4090 |
| Source | MSExchangeIMC |
| Description | Mail could not be delivered to <ip address> (for <domain name>). The destination server reported <error code> <description>; try again later. Delivery will be retried later. |
| Event Information | It is complaining that there are no MX or A records for SourceDomain.com. The sender address has to be something that mail can be sent back to. So this is an issue related to DNS. This may happen whenever the destination DNS server try to resolve the senders address, which is enforced by SMTP server to avoid unsolicited mail. |
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