Click here to Skip to main content
Click here to Skip to main content

Programmatically adding attachments to emails

, 18 Jan 2006 CPOL
Rate this:
Please Sign up or sign in to vote.
A technique for programmatically adding attachments to emails.


Having read Stephane Rodriguez's excellent and rather clever solution to programmatically adding attachments to Outlook emails, I realized how subtly useful this functionality was. Many was the time I have needed a way to send an application's document to another user. Obviously, it could be done by writing your own dialogs that mimic the mail client dialogs, but you have to hook up the address book and so on. It's far better to exploit the existing mail client software installed on the PC. I needed exactly this for an application so it could have File->Send To functionality - obviously, it needs attachments to work.

SendTo or MailTo

Stephane's article makes the perfectly valid point that using the SendTo approach is functionally better than using the mailto trick. Another compelling reason for not using mailto is it doesn't support attachments. The RFC mailto protocol is simple and doesn't specify attachments.

However, you commonly see code trying to use mailto like this: there 
  shipmate&Body=Here's the shipping 

It probably won't attach the document because you are at the liberty of the email client to implement the mailto protocol and include parsing for the attachment clause. You may not know what mail client is installed on the PC, so it may not always work - Outlook certainly doesn't support attachments using mailto.

So what's the best (and easiest) way to do it

Stephane's solution is neat. It simulates a drag 'n drop into Outlook by using an unpublished mail helper COM object. However, by using unpublished functionality, you are at the mercy of the vendor (in this case Microsoft) changing things! And this is what has happened. The drag drop code works with no problem at all when using Outlook 2002/2003 on Win2K, but throws a 'Privileged exception' when running on XP. The presumption is there are permission issues with this combination of OS and the version of Outlook.

I needed a mail client version independent solution that supported attachments, so I chose to investigate MAPI. As it turns out, the answer is pretty simple, which is wrapped up in the CSendFileTo class.

#ifndef __SENDFILETO_H__
#define __SENDFILETO_H__

#include <mapi.h>

class CSendFileTo
    bool SendMail(HWND hWndParent, 
         CString const &strAttachmentFileName, 
         CString const &strSubject=_T(""))
        // The attachment must exist as a file on the system
        // or MAPISendMail will fail, so......
        if (strAttachmentFileName.IsEmpty())
            return false;

        // You may want to remove this check, but if a valid
        // HWND is passed in, the mail dialog will be made
        // modal to it's parent.
        if (!hWndParent || !::IsWindow(hWndParent))
            return false;

        HINSTANCE hMAPI = ::LoadLibraryA(_T("MAPI32.DLL"));
        if (!hMAPI)
            return false;

        // Grab the exported entry point for the MAPISendMail function
                      MapiMessage*, FLAGS, ULONG);
        (FARPROC&)SendMail = GetProcAddress(hMAPI, 

        if (!SendMail)
            return false;

        TCHAR szFileName[_MAX_PATH];
        TCHAR szPath[_MAX_PATH];
        TCHAR szSubject[_MAX_PATH];
        ::StrCpy(szFileName, strAttachmentFileName.GetString());
        ::StrCpy(szPath, strAttachmentFileName.GetString());
        ::StrCpy(szSubject, strSubject.GetString());

        MapiFileDesc fileDesc;
        ::ZeroMemory(&fileDesc, sizeof(fileDesc));
        fileDesc.nPosition = (ULONG)-1;
        fileDesc.lpszPathName = szPath;
        fileDesc.lpszFileName = szFileName;

        MapiMessage message;
        ::ZeroMemory(&message, sizeof(message));
        message.lpszSubject = szSubject;
        message.nFileCount = 1;
        message.lpFiles = &fileDesc;

        // Ok to send
        int nError = SendMail(0, (ULONG_PTR)hWndParent, 
               &message, MAPI_LOGON_UI|MAPI_DIALOG, 0);

        if (nError != SUCCESS_SUCCESS && 
            nError != MAPI_USER_ABORT && 
            nError != MAPI_E_LOGIN_FAILURE)
              return false;

        return true;


Example use

This nugatory code fragment shows how easy it is to use.

#include "SendFileTo.h"

CSendFileTo sendTo;
sendTo.(m_hWnd, _T("c://documents//menu.doc"), 
                _T("Here's the lunch menu"));


This is all straightforward, but there are a few points to note.

  • If the attachment doesn't exist as a file on the file system, the call to MAPISendMail will fail with MAPI_E_ATTACHMENT_NOT_FOUND. Hence the check at the start of the SendMail call.
  • By passing the parent HWND to the MAPISendMail function, the email client is supposed to make the send mail dialog modal to the given HWND. You may want to remove this modalness(?) and simply use HWND_DESKTOP.
  • When the MAPISendMail call is made, it doesn't send the mail, it just pops up the email client dialog with the optional subject line set and the attachment attached.
  • This code was written to compile and work with WTL (it rocks), but will work equally well using MFC.

I've successfully tested this with Outlook 2002 and 2003 on Win2K and XP. I'd be interested in hearing if it works with other mail clients I don't have access to - Eudora etc.

This class could probably do with some more error checking but I'll leave that as an exercise for the reader.


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

David M Brooks
Technical Lead
United Kingdom United Kingdom
When Dave isn't trying to play drums, fly helicopters or race cars, he can be found coding hard and herding cats at JoinIn Networks He must try harder!

You can read Dave's ramblings in his blog Aliens Ate My GUI

Or, if you can be bothered, he twitters on BoomerDave

Comments and Discussions

QuestionGreat! PinmemberGiordano Settimo20-Mar-15 1:05 
QuestionGeneral comments PinmemberMadMalcolmX24-Oct-13 5:34 
QuestionNice, works now with wxwidgets as well PinmemberMember 90858329-Jul-12 9:12 
Questionsendto with attachment solution Pinmembermanywebbs9-Sep-11 19:14 
AnswerRe: sendto with attachment solution PinmemberRocky_Bas26-Sep-13 17:54 
GeneralMy vote of 5 Pinmemberitz_faraz5-May-11 20:31 
GeneralI hate to nag but this code sample is bad... Pinmemberdc_200025-Apr-11 18:46 
QuestionCan I use this solution for my problem.... Pinmemberdkperez21-Jan-10 13:16 
GeneralWARNING = THIS CODE PROBABLY UNSAFE Pinmembersashasawchai1-Dec-08 23:21 
GeneralRe: WARNING = THIS CODE PROBABLY UNSAFE PinmemberDavid M Brooks27-Aug-09 6:14 
It depends on how you clean things up when you've finished with them.

To counter the argument, I've used a variation of this code in a corporate application with a user base of over 1600. It's been running for over 3 years with no problems yet.

Generalto send more than 1 mail address [modified] PinmemberArielR2-Jul-08 11:08 
GeneralRe: to send more than 1 mail address Pinmemberpine_le11-Apr-10 5:28 
Questionwhat for ? Pinmemberkilt25-Jun-08 20:59 
QuestionLotus Notes ignores lpszFileName Pinmembertiggerlily30-Nov-07 0:08 
Questionwhy it saves the draft into inbox folder? Pinmemberxuxiaohui7-Nov-07 23:37 
QuestionNewbie problem - can't compile (get errors in mapi.h) Pinmembercgalpin1-Nov-07 5:59 
AnswerRe: Newbie problem - can't compile (get errors in mapi.h) PinmemberVarchas R S5-Nov-07 0:03 
GeneralRe: Newbie problem - can't compile (get errors in mapi.h) Pinmembercgalpin6-Nov-07 8:42 
QuestionSending html formatted email Pinmemberkryzzozz7810-Oct-07 10:09 
GeneralRe: Sending html formatted email PinmemberMember 216347031-Mar-08 5:56 
Generalprofile problem with MAPI Pinmemberrob010330-Jul-07 0:48 
GeneralRe: profile problem with MAPI PinmemberBhushanKalse27-Aug-07 21:28 
Generalthanks! Pinmembercronky7812-Jul-07 21:17 
Generalsending problem Pinmember133mmxtr11-Jun-07 3:20 
QuestionWCHAR version of Mapi32.dll ?? [modified] Pinmemberajitatif angajetor24-Jan-07 3:49 
AnswerRe: WCHAR version of Mapi32.dll ?? Pinmemberhannahb21-Mar-07 4:22 
GeneralRe: WCHAR version of Mapi32.dll ?? Pinmemberajitatif angajetor27-Mar-07 7:21 
Generalwants demo & source Pinmembershital_harode@rediffmail.com18-Nov-06 0:24 
GeneralRe: wants demo & source Pinmemberprathuraj6-Jun-07 0:10 
GeneralRe: wants demo & source PinmemberGeorge Zorba21-Mar-12 22:29 
GeneralAnyone know how to do this with C# Pinmemberc-a-b-24-Aug-06 9:49 
GeneralRe: Anyone know how to do this with C# [modified] PinmemberDavid Broooks12-Dec-06 5:01 
GeneralRe: Anyone know how to do this with C# Pinmemberc-a-b-12-Dec-06 11:31 
GeneralRe: Anyone know how to do this with C# PinmemberSriharsha R19-Jan-07 2:19 
AnswerRe: Anyone know how to do this with C# Pinmembergoondoo277-Feb-07 11:52 
GeneralRe: Anyone know how to do this with C# Pinmemberitz_faraz5-May-11 20:32 
GeneralRe: Anyone know how to do this with C# PinmemberDavid Broooks8-Feb-07 5:11 
GeneralAnti Virus issues PinmemberDavid Broooks23-May-06 12:34 
GeneralRe: Anti Virus issues - there's more.... PinmemberDavid Broooks23-May-06 12:45 
GeneralAutomatically Send and Multiple Attachments PinmemberJeffBilkey21-May-06 15:40 
GeneralRe: Automatically Send and Multiple Attachments PinmemberRishabh Agrawal18-Sep-06 20:05 
GeneralUnicode MFC compatible Multiple Attachment Pinmemberhannahb21-Mar-07 6:11 
QuestionTwo Questions? PinmemberSstar1-May-06 18:13 
AnswerRe: Two Questions? Pinmemberxuxiaohui7-Nov-07 23:05 
AnswerRe: Two Questions? Pinmembernovta20-Nov-07 5:02 
GeneralC++ Builder Version PinmemberJeffBilkey26-Apr-06 15:33 
GeneralRe: C++ Builder Version PinmemberJeffBilkey27-Apr-06 12:25 
GeneralRe: C++ Builder Version PinmemberJeffBilkey21-May-06 15:23 
GeneralRe: C++ Builder Version PinmemberOniko1126-May-06 1:24 
GeneralRe: C++ Builder Version PinmemberJeffBilkey29-May-06 17:14 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

| Advertise | Privacy | Terms of Use | Mobile
Web04 | 2.8.150414.1 | Last Updated 18 Jan 2006
Article Copyright 2006 by David M Brooks
Everything else Copyright © CodeProject, 1999-2015
Layout: fixed | fluid