Hi,

I've exactly same problem with Gareth, the only different is my DNN version is 5.1.1.

Following is my Event Log:

AssemblyVersion: 5.1.1
PortalID: 0
PortalName: PekoPiko
UserID: 3
UserName: henryhow
ActiveTabID: 108
ActiveTabName: SuggestPage
RawURL: /language/en-US/Find-Restaurant/SuggestPage.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: http://www.pekopiko.com/language/en-US/Find-Restaurant/SuggestPage.aspx
UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2 GTB5 (.NET CLR 3.5.30729)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 9d8cdfd1-d98a-4ec8-a19b-a48ea8b13da8
InnerException: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Net.Mail.MailCommand.CheckResponse
StackTrace:
Message: System.Net.Mail.SmtpException: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at at System.Net.Mail.MailCommand.CheckResponse(SmtpStatusCode statusCode, String response) at System.Net.Mail.MailCommand.Send(SmtpConnection conn, Byte[] command, String from) at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception) at System.Net.Mail.SmtpClient.Send(MailMessage message) at DotNetNuke.Services.Mail.Mail.SendMail(String MailFrom, String MailTo, String Cc, String Bcc, String ReplyTo, MailPriority Priority, String Subject, Mailformat Bodyformat, Encoding BodyEncoding, String Body, String[] Attachment, String SMTPServer, String SMTPAuthentication, String SMTPUsername, String SMTPPassword, Boolean SMTPEnableSSL)
Source:
Server Name: SKZ-B6647630761

Please help!