Why do some of my contacts not receive my emails?
Some of my contacts can't receive my emails. I get the following error messages:
"Remote host said: 553 5.1.3 bad address syntax"
"Remote host said: 501 Invalid Address [RCPT_TO]" "Remote host said: 501 Syntax error in parameters or arguments [RCPT_TO]"
I have talked to them personally and they say they aren't trying to block my messages.
The email addresses involved never used to give me a problem. Now it's every time.
すべての返信 (1)
are you requesting return or read receipts?