07 December 2007

System.Net.Mail.MailMessage Mail Header Casing Issue Fixed in .NET 2.0 SP1 & .NET 3.5

With the transition of MailMessage from System.Web.Mail to System.Net.Mail there were some mail header casing changes that caused mail sent to Hotmail and Live email addresses to appear as being successfully sent, but failed to arrive at the destination email address.  All headers were being sent all lower, which triggered spam filtering at the server.

I have verified that this issue has been fixed with .NET 2.0 SP1 & 3.5 which was just released a couple of weeks ago.  You can download the .NET 2.0 SP1 bits here: http://www.microsoft.com/downloads/details.aspx?FamilyId=79BC3B77-E02C-4AD3-AACF-A7633F706BA5&displaylang=en or you can install .NET 3.5, which includes 2.0 SP1 & 3.0 SP1 here: http://www.microsoft.com/downloads/details.aspx?FamilyId=333325FD-AE52-4E35-B531-508D977D32A6&displaylang=en

I don't have a work around for 2.0 bits, it's best to just upgrade to SP1.

Hope this helps,
Jon

 

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# Noticias externas said:

With the transition of MailMessage from System.Web.Mail to System.Net.Mail there were some mail header

07 December 07 at 6:22 PM
# Amigo mío Siempre estas Programando en .NET said:

El otro día repondiendo las preguntas de los foros de MSDN, me encontré con esta entrada: http

15 January 08 at 8:38 AM
# David Cardona said:

Hola.

Yo tengo el mismo problema pero es peor. Desde mi aplicacion win forms no se envia ningun correo y estoy seguro que mi odigo está bien, porque tal cual funciona perfectamente en una aplicacion web. No se porque desde una aplicacion Windows nunca me llegan los correos a cualquier destinatario. He intentado de todo pero nada. Lo peor es que no sale error. Desactive el cortafuegos y el antivirus y nada.

Otra cosa rara es que yo tengo el Framwork 2 SP 1

29 July 08 at 6:38 PM
# jongallant said:

David,

Did you look in your local mail root?

Does it fail for all email addresses or just hotmail/live acounts?

Jon

29 July 08 at 6:50 PM
# David Cardona said:

In English

_______________________________________

Hello Jongallant !

Thank you for responding.

It is for all directions. I have a normal email service and I know the direction my SMTP server. I also have an account and a key which is used as a credential for sending emails. It is very strange that the method SEND () runs but never receive emails.

I hope I can help. Thank you very much

En Español

_______________________________________

Hola

Gracias por responder.

Es para todas las direcciones. Yo tengo un servicio de email normal y yo conozco la direccion SMTP de mi servidor. Tambien tengo una cuenta y una clave que es la que uso como credencial para enviar los correos. Es muy extraño por que el metodo SEND() se ejecuta pero nunca recibo los correos.

Espero me puedas ayudar. Muchas gracias

31 July 08 at 12:37 PM
# jongallant said:

Is the mail reaching your Smtp server?  You should be able to setup a Trace or contact technical support for your Smtp host to see what is going on.  If you need further help I suggest you post a question on our forums.

http://forums.msdn.microsoft.com/

01 August 08 at 9:58 AM
# David Cardona said:

Hello

Thank you very much. I will look at the forum.

If I find the solution published here.

Again thanks

01 August 08 at 2:23 PM
# C#ristian said:

Pero y entonces? es el SP1 del Framework 2.0 lo q jode el envío de mails? porque yo no habia tenido problemas hasta un par de dias, todo por dejar las actualizaciones automáticas :@

Ahorita estoy desinstalando el SP1 del framework e instalaré de nuevo el 2.0 SIN Service Pack.

El problema es q las aplicaciones están hechas en 2.0, y no puedo migrarlas a 3.5.

Si alguien sabe algo al respecto, mi correo es freezer27@gmail.com

27 February 09 at 2:52 PM

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