Field not set: ParentEPSObjectId when creating Project.

Question

Hi everyone,
I'm developing .net application and getting data from primavera by using p6 web service. At the moment I stuck on project creation. I'm using following code to create a new project:
Public Function CreateOneProject(pProjectName As String, pProjectId As String, pParentEpsObjectId As Integer, pPlannedStart As Date, pPlannedFinish As Date, pParentOBSObjectId As Integer) As Integer
     Dim vNewProject As Project()
     vNewProject = New Project(0) {}
     Dim vProject As New Project()
     vProject.Name = pProjectName
     vProject.Id = pProjectId
     vProject.ParentEPSObjectId = pParentEpsObjectId
     vProject.StartDate = pPlannedStart
     vProject.FinishDate = pPlannedFinish
     vProject.OBSObjectId = pParentOBSObjectId
     vNewProject(0) = vProject
     Dim retVal As Integer() = gProjectService.CreateProjects(vNewProject)
     Return retVal(0)
End Function
And getting error message: Field not set:ParentEPSObjectId when creating Project.
EPS Object ID i'm selecting from lookup. In this lookup datasource I have following fields from ReadEPS: ObjectId, Name, Id, ParentObjectID.
As I understood, I should to get ObjectID of selected EPS and to set as parameter in CreateOneProject function. But it's not working.
Could someone help me?
Best regards,
Dmitrij

Answer 1

I found what was the problem.
Did not specify following field: ParentEPSObjectIdSpecified = true. With this field I can save.