its code for detach email
// Use below code.
// Rreplace the WebService URL
service.Url = strWebServiceURL;
service.Credentials = System.Net.CredentialCache.DefaultCredentials;
DetachFromQueueEmailRequest objEmail = new DetachFromQueueEmailRequest();
// Assign Email GUID
objEmail.EmailId = new Guid(strEmailGUID.Trim());
// Assign Queue GUID
objEmail.QueueId = new Guid(QueueIdNode.InnerText.Trim().ToString());
service.Execute(objEmail);
For More see MS CRM Support section
http://support.microsoft.com/ph/12976
Regards,
Imran
http://www.crmxperts.com