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Connection refused Socket Error # 10061



I am trying to test email but on the SMTP sensor I am getting the error:

Connection refused Socket Error # 10061 Connection refused. (socket error # 10061)

There is no software firewall on the server, I can telnet to port 25 fine and I have tried every format of authentication credentials possible (domain\username, username, username@domain etc) with several accounts.

Is there some obvious reason why I am getting this error?

error smtp

Created on Nov 3, 2011 5:05:11 PM

1 Reply

Accepted Answer



if you can telnet to the smtp port, have you tried to send an email manual by typing the message in the telnet window? If not you can do this this way, which will give you a more detailed view what went wrong sending mail:

Obviously telnet from your prtg server to your mailserver:

"telnet <yourmyilserver>"

You should get something like: " 220 * SMTP Server Ready"

Type "HELO test"

You shoud get: "250 Hello test, pleased to meet you"

Type "MAIL FROM: [email protected]"

You shoud get: "250 [email protected] OK"

Type "RCPT TO: "<your_destination_mailaddress>"

You shoud get: "250 <your_destination_mailaddress> ... Recipient ok"

Type "DATA"

You shoud get: "354 Start Mail input, end with <CRLF>.<CRLF>"

Type "SUBJECT: Telnet Test <CR>" Lore ipsum...<CR> <CR> .<CR>

You shoud get: "250 OK"

after that your mail is send. if there is a break in the process described above, the returning SMTP code should give you more info on what went wrong.

You shoud get: "354 Start Mail input, end with <CRLF>.<CRLF>"

Created on Nov 9, 2011 7:28:30 PM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.