01Nov
SMTP Error Codes
SMTP Error Codes4xx Error Codes 5xx Error CodesWhen messages are sent or received between two email servers or Mail Transfer Agents (MTAs), the communication uses a series of numeric SMTP codes. These codes are always in pairs, which means both servers transmit the codes until either the conversation is successful, or fails.There are two main code types for dropped or failed SMTP conversations. The first number in a code, indicates whether the MTA accepted the command, or if it was [...]
