The email attachment name contains non-ASCII characters and exceeds 41 UTF-8 encoded bytes. The transfer encoding is twice in the previous. NET Framework 4 compiled application.

From: http://support.microsoft.com/kb/2402064 Symptom Consider the following situations: Run an application compiled by Microsoft. NET Framework 4Program. Application callSystem. net. smtpclientClass to send emails andAttachmentClass is used to attach a fileEmailObject. The attachment name contains non-ASCII characters, in bytes exceeding 41 UTF-8 encoding ). In this case, the attachment name is accidentally transferred twice before encoding.The email message receiver then truncates the encoded name, but does not search for attachments in the original name. Cause This problem occurs because of a problem in. NET Framework 4.SMTP encoding is overwritten to include RFC standards that properly fold the length limit of each line.This will insert an additional carriage return line break (CRLF) character name string is too long.These additional control characters recode the attachment name. Solution Patch Information You can now obtain supported patches from Microsoft.However, it is used to solve the problems described in this article.It is only applicable to systems that encounter this specific problem.This patch may undergo further testing.Therefore, if this issue does not have a serious impact on you, we recommend that you wait for the next software update that contains this patch. To resolve this issue immediately, contact Microsoft customer support for this fix.For a complete list of Microsoft customer support service phone numbers and support charges, visit the following Microsoft Website: Http://support.microsoft.com/contactus? Ws = Support Note:In special circumstances, if Microsoft support professionals confirm that a specific update will solve your problem, it may be canceled, which will usually cause the support phone fee.Other support problems and issues, which are not suitable for specific updates, will be charged normally. Note:You can download this summary from the following Microsoft connection Website: Https://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx? Downloadid = 31723 Essential Components You must have Microsoft. NET Framework 4 installed to apply this patch. Restart Information You do not need to apply this patch to restart the computer. File Information This patch is listed in the file attributes (or updated file attributes) Table in English version.Date and time, which are listed in Coordinated Universal Time (UTC ).When you view the file information, it is converted to the local time.To learn the time difference between UTC and local time, go toDate and TimeUsed inTime ZoneTab. Supports all x86 versions of Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2 x File Name File version File Size Date Time Platform Setupui. dll 10.0.30319.364 295,248 September 28, 2010 05: 19 X86 Setupengine. dll 10.0.30319.364 809,304 September 28, 2010 05: 19 X86 Setup.exe 10.0.30319.364 78,152 September 28, 2010 05: 19 X86 System. dll 4.0.30319.364 3,482,440 September 28, 2010 11: 15 X86 All Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2 versions based on x64 are supported. File Name File version File Size Date Time Platform Setupui. dll 10.0.30319.364 295,248 September 28, 2010 05: 19 X86 Setupengine. dll 10.0.30319.364 809,304 September 28, 2010 05: 19 X86 Setup.exe 10.0.30319.364 78,152 September 28, 2010 05: 19 X86 System. dll 4.0.30319.364 3,482,440 September 28, 2010 11: 15 X86 For all Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2 that are supported based on IA 64 File Name File version File Size Date Time Platform Setupui. dll 10.0.30319.364 295,248 September 28, 2010 05: 19 X86 Setupengine. dll 10.0.30319.364 809,304 September 28, 2010 05: 19 X86 Setup.exe 10.0.30319.364 78,152 September 28, 2010 05: 19 X86 System. dll 4.0.30319.364 3,482,440 September 28, 2010 11: 15 X86