About Noreply Account
What is noreply mailbox? Noreply is a system reserved account. Normally, it is used to send bounce, auto reply, auto forward mail and so on. If a mailbox sends mail failed, AAMail will send a bounce to this mailbox with noreply account. In the bounce, it generally will include the reasons, which offered a direction for the administrator to analyze the problem. And this is a normal phenomenon.
If there is something like "noreply@maifom.null (127.0.0.1)", it indicates that someone is sending mails with an empty mail account, that is, "MAILFROM: <>".
Usually, this is because your mailbox's password is too simple, it will be cracked by others very easily. Then, plenty of spams will be sent to you, and simply, your server was attacked. Because you need to send and receive mails to and from other mailboxes in the Internet, the port 25 of the mail server system needs to be opened to the entire Internet, Which provides opportunities for some spammers to use their tools to scan and crack the email passwords by brute force, thus obtaining the sending permission, and sending a lot of spams via your mail server. Then, in AAMail "Mail sending" list (click the "Status" on the left side of AAMail main interface), you will see hundreds of mails are constantly sending out, which will certainly cause the server congestion, and then the mail server can not receive and send mails normally.
Solution:
1) Modify all the accounts' passwords to complex ones, such as "letters + numbers + special symbols", and the password length is not less than 8.
2) Prevent "noreply" account from sending mails. But Outlook will not be able to send the receipt.
The steps about how to prevent "noreply" account from sending mails are as follows.
1) In AAMail main interface, on the toolbar, click the "Settings" (Figure 1-1).
Figure 1-1
2) In the pop up "Server settings" dialog box, click the "Network" tab, uncheck the "SMTP allow empty MAILFROM command (<>)" check box (Figure 1-2).
Figure 1-2
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