Returned e-mail

[RA]

Hello All, Every day I receive a lot of returned mails but don't know the reason. Please see. bellow is the simple copy-paste version of one such mail. How it is possible to prevent these. Any help is appreciated.   Thanks.   ----- Original Message ----- From: "Mail Delivery Subsystem" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, November 16, 2002 10:32 AM Subject: Returned mail: User unknown > The original message was received at Sat, 16 Nov 2002 01:01:00 -0500 (EST) > from  [195.250.78.242] > > > *** ATTENTION *** > > Your e-mail is being returned to you because there was a problem with its > delivery.  The address which was undeliverable is listed in the section > labeled: "----- The following addresses had permanent fatal errors -----". > > The reason your mail is being returned to you is listed in the section > labeled: "----- Transcript of Session Follows -----". > > The line beginning with "<<<" describes the specific reason your e-mail could > not be delivered.  The next line contains a second error message which is a > general translation for other e-mail servers. > > Please direct further questions regarding this message to your e-mail > administrator. > > --AOL Postmaster > > > >    ----- The following addresses had permanent fatal errors ----- > <[EMAIL PROTECTED]> > <[EMAIL PROTECTED]> > <[EMAIL PROTECTED]> > >    ----- Transcript of session follows ----- > ... while talking to air-xj04.mail.aol.com.: > >>> RCPT To:<[EMAIL PROTECTED]> > <<< 550 MAILBOX NOT FOUND > 550 <[EMAIL PROTECTED]>... User unknown > >>> RCPT To:<[EMAIL PROTECTED]> > <<< 550 MAILBOX NOT FOUND > 550 <[EMAIL PROTECTED]>... User unknown > >>> RCPT To:<[EMAIL PROTECTED]> > <<< 550 MAILBOX NOT FOUND > 550 <[EMAIL PROTECTED]>... User unknown >