You can send email using traditional user/password authentication from Office 365 account by EWS Protocol.
However Microsoft will disable traditional user authentication in the future, switching to Microsoft OAuth (Modern Authentication) is strongly recommended now.
EASendMail is a SMTP component which supports all operations of SMTP/ESMTP protocols (RFC 821, RFC 822, RFC 2554). Before you can use the following example codes, you should download the EASendMail Installer and install it on your machine at first.
To use EASendMail SMTP ActiveX Object in your project, the first step is “Add reference
of EASendMail to your project”. Please select menu ->
EASendMailObj ActiveX Object, click
OK, the reference will be added
to current project, and you can start to use it to send email in your VB6 project.
Open VBA IDE by press
Alt+F11, Please select menu ->
References -> and select
EASendMailObj ActiveX Object,
click OK, the reference will be added to current VBA project, and you can start to use it to send email in your VBA project.
Normal OAuth requires user input user/password for authentication. Obviously, it is not suitable for background service. In this case, You can use the OAuth 2.0 client credentials grant, sometimes called two-legged OAuth, to access web-hosted resources by using the identity of an application. It only works for Office365 user, it doesn’t work for personal Hotmail account.
To use Microsoft/Office365/Live OAuth (Modern Authentication) in your application, you must create a application in https://portal.azure.com.
You can use any Microsoft user to create the application, it doesn’t require application owner is administrator in your Office365 domain. But your Office365 administrator must authorize the application to access user mailbox.
Sign in to the Azure portal using either a work or school account or a personal Microsoft account.
If your account gives you access to more than one tenant, select your account in the top right corner, and set your portal session to the Azure AD tenant that you want.
In the left-hand navigation pane, select the Azure Active Directory service, and then select
App registrations ->
When the Register an application page appears, enter your application’s registration information:
"in any organizational directory and personal Microsoft accounts".
Redirect URI (optional)
Select the type of app you’re building, Web or Public client (mobile & desktop), and then enter the redirect URI (or reply URL) for your application.
For web applications, provide the base URL of your app. For example,
http://localhost:31544might be the URL for a web app running on your local machine. Users would use this URL to sign in to a web client application.
For public client applications, provide the URI used by Azure AD to return token responses. Enter a value specific to your application, such as myapp://auth.
After you registered your application, Azure AD assigns a unique application (client) ID to your app,
and you’re taken to your application’s Overview page.
"Certificates and secrets" ->
"client secrets" and add a new client secret.
"client secret" by yourself, because it is hidden when you view it at next time.
"API Permission" ->
"Add a permission" ->
"Application permissions" ->
"Check full_access_as_app" ->
"Add a permission" ->
"Microsoft Graph" ->
"Delegated Permission" ->
"User.Read", "email", "offline_access", "openid" and "profile".
Implicit grant: check
Redirect URI: input the url to get authorization code, for native desktop application, you don’t have to add redirect uri.
Mobile and desktop applications ->
Redirect Uri, please check or add the following URI.
https://login.microsoftonline.com/common/oauth2/nativeclient https://login.live.com/oauth20_desktop.srf http://127.0.0.1
https://login.live.com/oauth20_desktop.srfis used for Live SDK,
http://127.0.0.1is used for local Http Listener.
Supported account types:
Select Accounts in any organizational directory (Any Azure AD directory - Multitenant) and personal Microsoft accounts (e.g. Skype, Xbox)
"Live SDK Support" and
"Treat application as a public client" to
client id and
client secret support both
"Office365 + EWS" and
"Live (hotmail, outlook personal account) + SMTP",
Office365 OAuth doesn’t support SMTP with Application permissions, only EWS is supported.
To use your application to access user mailbox in Office365 domain, you should get admin consent by Office365 domain administrator.
If you created the application and you’re the Office365 administrator:
API Permission ->
"Click grant admin consent for ..." to grant consent to the application.
If you created the application and you’re not the Office365 administrator:
Send the link to Office365 administrator, please change
client_id to yours
Administrator can open above link in web browser, if administrator agrees with the permissions the application requires, grant consent. If not, click cancel or close the window.
Administrator can change/cancel the permissions by Sign in to the
Azure Portal -> Select
Azure Active Directory then
After administrator granted consent, web browser will redirect to the following URL, send tenant value to application developer.
After administrator authorized the permissions, you can use your application to access any users mailbox in Office365 domain.
You should create your
client id and
client secret, do not use the
client id from example codes in production environment,
it is used for test purpose.
Option Explicit Const ConnectNormal = 0 Const ConnectSSLAuto = 1 Const ConnectSTARTTLS = 2 Const ConnectDirectSSL = 3 Const ConnectTryTLS = 4 Const AuthAuto = -1 Const AuthLogin = 0 Const AuthNtlm = 1 Const AuthCramMd5 = 2 Const AuthPlain = 3 Const AuthMsn = 4 Const AuthXoauth2 = 5 Private Function GenerateRequestData() Const client_id = "8f54719b-4070-41ae-91ad-f48e3c793c5f" Const client_secret = "cbmYyGQjz[d29wL2ArcgoO7HLwJXL/-." Const scope = "https://outlook.office365.com/.default" GenerateRequestData = "client_id=" & client_id & "&client_secret=" & client_secret & "&scope=" & scope & "&grant_type=client_credentials" End Function Private Function RequestAccessToken(requestData) RequestAccessToken = "" If requestData = "" Then Exit Function End If On Error GoTo ErrorHandle Dim httpRequest Set httpRequest = CreateObject("MSXML2.ServerXMLHTTP") ' If your application is not created by Office365 administrator, ' please use Office365 directory tenant id, you should ask Offic365 administrator to send it to you. ' Office365 administrator can query tenant id in https://portal.azure.com/ - Azure Active Directory. Const tenant_id = "79a42c6f-5a9a-439b-a2ca-7aa1b0ed9776" Dim tokenUri tokenUri = "https://login.microsoftonline.com/" & tenant_id & "/oauth2/v2.0/token" httpRequest.setOption 2, 13056 httpRequest.Open "POST", tokenUri, True httpRequest.setRequestHeader "Content-Type", "application/x-www-form-urlencoded" httpRequest.Send requestData Do While httpRequest.ReadyState <> 4 DoEvents httpRequest.waitForResponse (1) Loop Dim Status Status = httpRequest.Status If Status < 200 Or Status >= 300 Then MsgBox "Failed to get access token from server." MsgBox httpRequest.responseText Exit Function End If Dim result result = httpRequest.responseText Dim oauthParser As New EASendMailObjLib.OAuthResponseParser oauthParser.Load result Dim accessToken accessToken = oauthParser.accessToken If accessToken = "" Then MsgBox "Failed to parse access token from server response." Exit Function End If RequestAccessToken = accessToken Exit Function ErrorHandle: MsgBox "Failed to request access token." & Err.Description End Function Public Sub SendEmail() Dim accessToken As String accessToken = RequestAccessToken(GenerateRequestData()) If accessToken = "" Then Exit Sub End If Dim Office365User As String Office365User = "email@example.com" Dim oSmtp As EASendMailObjLib.Mail Set oSmtp = New EASendMailObjLib.Mail oSmtp.LicenseCode = "TryIt" ' Office365 server address oSmtp.ServerAddr = "outlook.office365.com" ' Set Exchange Web Service Protocol - EWS - Exchange 2007/2010/2013/2016/2019/Office365 oSmtp.Protocol = 1 ' Enable SSL/TLS connection oSmtp.ConnectType = ConnectSSLAuto ' OAUTH/XOAUTH2 type oSmtp.AuthType = AuthXoauth2 oSmtp.UserName = Office365User oSmtp.Password = accessToken oSmtp.FromAddr = Office365User oSmtp.AddRecipient "Support Team", "firstname.lastname@example.org", 0 oSmtp.BodyText = "Hello, this is a test...." If oSmtp.SendMail() = 0 Then MsgBox "Message delivered!" Else MsgBox oSmtp.GetLastErrDescription() End If End Sub
TLS is the successor of SSL, more and more SMTP servers require
TLS 1.2 encryption now.
If your operating system is
Windows XP/Vista/Windows 7/Windows 2003/2008/2008 R2/2012/2012 R2, you need to
enable TLS 1.2 protocol in your operating system like this: