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Server Error in '/mail' Application.

The server rejected one or more recipient addresses. The server response was: 550 5.7.1 Unable to relay for taha_tmm@yahoo.com

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Runtime.InteropServices.COMException: The server rejected one or more recipient addresses. The server response was: 550 5.7.1 Unable to relay for taha_tmm@yahoo.com

Source Error:

Line 43: }Line 44: SmtpMail.SmtpServer="Localhost";Line 45: SmtpMail.Send(msg);Line 46: Line 47: }

Source File: e:\d\Project\Visual Studio Projects\project of ASP.net\Summer\mail with attachment\mail.aspx.cs Line: 45

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