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Error: "554 Message not allowed - "
The error message below arises as a result of the sender computer's date and time not being set correctly:
Indeed, Yahoo's mail servers check this information and so you will need to update these details and try to send the messages again.
----- The following addresses had permanent fatal errors -----
(reason: 554 Message not allowed - )
----- Transcript of session follows -----
... while talking to g.mx.mail.yahoo.com.:
<<< 420 Resources unavailable temporarily. Please try later
... while talking to b.mx.mail.yahoo.com.:
<<< 554 Message not allowed - 
554 5.0.0 Service unavailable
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