Ok Thanks
 Generally, you don't want to take information from the exception and send it directly to the client as this can expose security holes & proprietary code.  Instead you find out what exception you have encountered in the Try...Catch and then you write whatever you find to be appropriate to the client based on that information.  If you really want to include exception information directly in your output, it is a simple matter of concatenation:

 ClientScript.RegisterStartupScript(Me.GetType(), "E-Mail Problem", String.Format("Alert('There was a {0} problem in sending the email! Please call us by phone {1}');", ex.GetType.ToString(), smtpEx.Message.Replace("'", "\'")), True)

   "JoeP" <NoSpam@Hotmail.com> wrote in message news:eLETt1xRIHA.4180@TK2MSFTNGP06.phx.gbl...
   My question is now how can I concatenate the 2 strings together into the message box for the Alert()?

   ClientScript.RegisterStartupScript(Me.GetType(), "E-Mail Problem", String.Format("Alert('There was a problem in sending the email! Please call us by phone {0}');", smtpEx.Message.Replace("'", "\'")), True)

   String 1 is: 'There was a problem in sending the email! Please call us by phone!
   String 2 is:smtpEx.Message

   Thanks.

   "Scott M." <smar@nospam.nospam> wrote in message news:OAtGO$pRIHA.4180@TK2MSFTNGP06.phx.gbl...
     When you are in a Catch section, notice that the exception is passed to the catch as "ex".  If you check out the properties of "ex", you can find out about the exception.  Start with this:

     Catch ex As Exception
         console.writeline("Exception type is: " & ex.getType.toString)
         console.writeline("Exception message is: " & ex.Message)

       "JoeP" <NoSpam@Hotmail.com> wrote in message news:%23XxCPgpRIHA.4476@TK2MSFTNGP06.phx.gbl...
       Hi All,

       Ok, after checking into it I had some code after the End Try and that was the reason Alert() did not pop up.
       Moving that code under the Try fixed the problem.

       But I am trying to break the message into 2 lines:

       ClientScript.RegisterStartupScript(Me.GetType(), "E-Mail Problem", String.Format("Alert('There was a problem in sending the email! Please call us by phone {0}');", smtpEx.Message.Replace("'", "\'")), True)

       Now how do I bring the actual err line into the second line of the Alert()

       There was a problem in sending the email! Please call us by phone.
       Unable to cast object of type 'System.Int32' to type 'System.Net.Mail.MailMessage'

       Thanks,

       Joe

         "JoeP" <NoSpam@Hotmail.com> wrote in message news:eGeSbJpRIHA.5988@TK2MSFTNGP02.phx.gbl...
         Well I had actuallt the code like the below: The debugger poped up and just said that the Failure sending mail.
         and did not provide the reason. But from some reason in my computer under Visual Studio 2005, the Alert message did not pop up.
         Just wondering why? (The debugger did).

         Thanks,

         Joe

         Try
             some code.....
             oMailMessage.IsBodyHtml = False
             oMailMessage.Body = cEmailBody

             Dim oSMTP As New SmtpClient
             oSMTP.Send(oMailMessage)   (in this line I am getting the above err)

         Catch smtpEx As SmtpException
             ClientScript.RegisterStartupScript(Me.GetType(), "E-Mail Problem", String.Format("Alert('There was a problem in sending the email: {0}');", smtpEx.Message.Replace("'", "\'")), True)

         Catch generalEx As Exception

             ClientScript.RegisterStartupScript(Me.GetType(), "General Problem", String.Format("alert('There was a general problem: {0}');", generalEx.Message.Replace("'", "\'")), True)

         End Try

         "Scott M." <smar@nospam.nospam> wrote in message news:%23lIk0%23cRIHA.4444@TK2MSFTNGP02.phx.gbl...
           Wrap the code in a try...catch block?

             "JoeP" <NoSpam@Hotmail.com> wrote in message news:%23i4RTOcRIHA.3516@TK2MSFTNGP02.phx.gbl...
             Hi All,

             How can I find the reason for such an error: Failure sending mail.

             Some Code...

             oMailMessage.IsBodyHtml = False
             oMailMessage.Body = cEmailBody
             Dim oSMTP As New SmtpClient
             oSMTP.Send(oMailMessage)   (in this line I am getting the above err)

             Appreciate any feedback

             Thanks,

             Joe