Sending emails using PHP in WINDOWS

In WINDOWS, I used PHP to send emails. I moved the program running in LINUX to WINDOWS. the following error occurs when I send emails: Warning: & nbsp; mail () & nbsp; [function. mail]: & nbsp; SMTP & nbsp; server & nbsp; response sending mails in PHP in WINDOWS
When I move the program running in LINUX to WINDOWS, the following error occurs when I send an email:
Warning: mail () [function. mail]: SMTP server response: 550 5.7.1 Unable to relay for cosmos_library@cosmel.com in D: \ websites \ cosmel_com \ elink \ reply2.php on line 12
Email system error!


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The 12 lines of reply2.php code are as follows:

Mail ("cosmos_library@cosmel.com", "HELLO", $ body, "From: $ yourmail") or die ("Email system error! ");

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How can this problem be solved?
(Note: in WINDOWS, I have started the SMTP service)

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Or your Smtp Server problems
Port 25 is connected, but cannot be sent

Configure
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Same as above. if it still doesn't work, try sending an email using the client.
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Google
Php smtp class free down
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Dog... Search