[BSvetlana]

Вот мой вариант. Может, почерпнете что-нибудь из этого

string orgName = Request.QueryString["orgname"];
ViewState["orgname"] = orgName;

CrmAuthenticationToken token = new CrmAuthenticationToken();
token.AuthenticationType = 0;
token.OrganizationName = orgName;

CrmService service = new CrmService();
service.CrmAuthenticationTokenValue = token;
service.Credentials = System.Net.CredentialCache.DefaultCredentials;

Guid userid = new Guid();
WhoAmIRequest userRequest = new WhoAmIRequest();
WhoAmIResponse currentUser = (WhoAmIResponse)service.Execute(userRequest);

userid = currentUser.UserId;

task task = new task();
//string correctDateTime = "2009-05-08T12:00:00";
string correctDateTime = "";

string year = idDate.Text.Substring(6, 4);
string month = idDate.Text.Substring(3, 2);
string day = idDate.Text.Substring(0, 2);

// Set the task subject.
task.subject = subjectText.Text;

string time = idTime.SelectedItem.Text;

string hour = "";
string minute = "";
hour = time.Substring(0, 2);
minute = time.Substring(3, 2);

// Set the date of the task.
correctDateTime = year + "-" + month + "-" + day + "T" + hour + ":" + minute + ":00";

task.scheduledstart = new CrmDateTime();
task.scheduledstart.Value = correctDateTime;

//Set the regardingobject
task.regardingobjectid = new Lookup();
task.regardingobjectid.Value = new Guid(regardingobjectidHidden.Value);
task.regardingobjectid.type = EntityName.account.ToString();

//Set the user
task.ownerid = new Owner();
task.ownerid.Value = user.UserId;
task.ownerid.type = EntityName.systemuser.ToString();
if (descriptionText.Text != "")
{
task.description = descriptionText.Text;
}


//Try to create the task
Guid createdTaskId = service.Create(task);

#region check success
Boolean success = false;
if (createdTaskId != Guid.Empty)
{
success = true;

}

Log("Task success " + success);


Что-то вроде.....