SMTP Response 252
Description: Can not verify user; accepting message for attempt.
What does this mean?
The message was received properly, and there is some positive record of the email address existing. However, it’s most likely not on the delivered mail server and being held until verification is possible. 95% of the time, this message will be delivered as expected.
How to fix SMTP Error 252?
The email message should be delivered with out an issue, however it would be wise to monitor the email log for any other indications that it failed. If a failure occurs, it’s best to ensure the email address is correct.