How I can send emails using the client object model?

Question

I have tried this, but I always get an exception with error message "A recipient must be specified.":
string webUrl = "http://sharepoint.example.com/";
EmailProperties properties = new EmailProperties();
properties.To = new string[] { "[email protected]" };
properties.Subject = "Test subject";
properties.Body = "Test body";
ClientContext context = new ClientContext(webUrl);
Utility.SendEmail(context, properties);
context.ExecuteQuery(); // ServerException thrown here
context.Dispose();
Server stack trace:
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Microsoft.SharePoint.Utilities.SPUtility.SendEmail_Client(EmailProperties properties)
at Microsoft.SharePoint.ServerStub.Utilities.SPUtilityServerStub.InvokeStaticMethod(String methodName, XmlNodeList xmlargs, ProxyContext proxyContext, Boolean& isVoid)
at Microsoft.SharePoint.Client.ServerStub.InvokeStaticMethodWithMonitoredScope(String methodName, XmlNodeList args, ProxyContext proxyContext, Boolean& isVoid)
at Microsoft.SharePoint.Client.ClientMethodsProcessor.InvokeStaticMethod(String typeId, String methodName, XmlNodeList xmlargs, Boolean& isVoid)
at Microsoft.SharePoint.Client.ClientMethodsProcessor.ProcessStaticMethod(XmlElement xe)
at Microsoft.SharePoint.Client.ClientMethodsProcessor.ProcessOne(XmlElement xe)
at Microsoft.SharePoint.Client.ClientMethodsProcessor.ProcessStatements(XmlNode xe)
at Microsoft.SharePoint.Client.ClientMethodsProcessor.Process()
msdn link: http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.client.utilities.utility.sendemail.aspx

Answer 1

hi
if you will check the code of SendEmail_Client(EmailProperties properties), you will find that it may only send emails to internal users. May be it was made intentionally in order to prevent spamming from client code. So let's see:
internal static void SendEmail_Client(EmailProperties properties)
if (properties.To.Count == 0)
throw new SPException(SPResource.GetString(web.LanguageCulture, "SendEmailInvalidRecipients", new object[0]));
AddressReader func = null;
using (MailMessage mm = new MailMessage())
func = delegate (MailAddress a) {
mm.To.Add(a);
ResolveAddressesForEmail(web, properties.To, func);
new SmtpClient(SPAdministrationWebApplication.Local.OutboundMailServiceInstance.Server.Address).Send(mm);
I.e. it adds recipient in ResolveAddressesForEmail() method. Now let's check this method:
private static void ResolveAddressesForEmail(SPWeb web, IEnumerable<string> addresses, AddressReader func)
if (addresses != null)
foreach (string str in addresses)
if (string.IsNullOrEmpty(str))
continue;
SPPrincipalInfo info = ResolvePrincipal(web, str, SPPrincipalType.All, SPPrincipalSource.All, null, false);
if ((info != null) && (info.PrincipalId > 0))
if (!string.IsNullOrEmpty(info.Email))
try
func(new MailAddress(info.Email, (info.DisplayName != null) ? info.DisplayName : "", Encoding.UTF8));
catch (FormatException)
continue;
if ((string.IsNullOrEmpty(info.Email) && info.IsSharePointGroup) && web.DoesUserHavePermissions(SPBasePermissions.BrowseUserInfo))
SPGroup byNameNoThrow = web.SiteGroups.GetByNameNoThrow(info.LoginName);
if (byNameNoThrow == null)
continue;
foreach (SPUser user in byNameNoThrow.Users)
if (!string.IsNullOrEmpty(user.Email))
try
func(new MailAddress(user.Email, (user.Name != null) ? user.Name : "", Encoding.UTF8));
continue;
catch (FormatException)
continue;
continue;
I.e. at first it tries to resolve user using ResolvePrincipal() method. If it is not resolved (info == null) email is not sent. But if it is - it first checks that email is not empty. If it is not - it adds email to the MailMessage.To recipients list. If
it is empty it checks whether the principal info represents Sharepoint group. If yes - it will send email to each member of the group.
So it may be so that you try to send email to external user (which is not supported according to the code above), or resolved principal doesn't have email specified.
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