InvalidGroupUIDRef....Why ??????

SvcResource.ResourceDataSet resNewDs = new SvcResource.ResourceDataSet();
                    SvcResource.ResourceDataSet.ResourcesRow resourceRow = resNewDs.Resources.NewResourcesRow();
                    NewResGuid = Guid.NewGuid();
                    resourceRow.RES_UID = NewResGuid;
                    resourceRow.RES_NAME = Name;
                    resourceRow.WRES_EMAIL = Email;
                    resourceRow.RES_INITIALS = Name.Substring(0, 1) +
                                        (Name.IndexOf(" ") > 0 ? Name.Substring(Name.IndexOf(" ") + 1, 1) : "");
                    resourceRow.RES_TYPE = (int)PSLibrary.Resource.Type.PureUser;
                    //resourceRow.RES_GROUP = "Project Managers";
                    resNewDs.Resources.AddResourcesRow(resourceRow);
                    Res.CreateResources(resNewDs, false, true);
                    System.Threading.Thread.Sleep(2000);
                    // Upgrade user using the Authorization dataset,...
                    SvcResource.ResourceAuthorizationDataSet resourceAuthDs = new SvcResource.ResourceAuthorizationDataSet();
                    SvcResource.ResourceAuthorizationDataSet.ResourcesRow resourceAuthRow = resourceAuthDs.Resources.NewResourcesRow();
                    resourceAuthRow.RES_UID = NewResGuid;
                    if (NTAccountName.Contains("aspnetsqlmembershipprovider"))
                    {
                        resourceAuthRow.RES_IS_WINDOWS_USER = false;
                    }
                    else
                    {
                        resourceAuthRow.RES_IS_WINDOWS_USER = true;
                    }
                    resourceAuthRow.WRES_ACCOUNT = NTAccountName;                    
                    resourceAuthDs.Resources.AddResourcesRow(resourceAuthRow);
                    Res.SetResourceAuthorization(resourceAuthDs);
                    System.Threading.Thread.Sleep(2000);
                    //conPublished= new SqlConnection(p.ReadXML("PublishedCon"));
                    //if (conPublished.State == ConnectionState.Closed) conPublished.Open();
                    //SqlCommand cmd = new SqlCommand("INSERT INTO MSP_WEB_SECURITY_GROUP_MEMBERS (WRES_GUID,WSEC_GRP_GUID) VALUES ('" + NewResGuid + "','" + p.ReadXML("WSEC_GRP_GUID") + "')", conPublished);
                    //cmd.ExecuteNonQuery();
                    //conPublished.Close();
                    SvcSecurity.SecurityGroupsDataSet secGpDS = new SvcSecurity.SecurityGroupsDataSet();
                    SvcSecurity.SecurityGroupsDataSet.SecurityGroupsRow groupDs = null;
                    secGpDS = Sec.ReadGroupList(); //Read all the Groups availabl in the Project Server 2010
                    Guid GroupUID = new Guid();
                    foreach (SvcSecurity.SecurityGroupsDataSet.SecurityGroupsRow ds in secGpDS.SecurityGroups)
                    {
                        if (ds.WSEC_GRP_NAME == "Project Managers")
                        {
                            groupDs = ds;
                            break;
                        }
                    }
                    //Assign the Resource respective user to Project Managers Group and Move Further...
                    SvcSecurity.SecurityGroupsDataSet dsGd = new SvcSecurity.SecurityGroupsDataSet();
                    SvcSecurity.SecurityGroupsDataSet.GroupMembersRow securityGroupMembersRow = dsGd.GroupMembers.NewGroupMembersRow();
                    securityGroupMembersRow.RES_UID = NewResGuid;
                    securityGroupMembersRow.WSEC_GRP_UID = new Guid("14D044FC-86D6-4271-AF83-39AD5F139013");
                    dsGd.GroupMembers.AddGroupMembersRow(securityGroupMembersRow);
                    Sec.SetGroups(dsGd);
                    System.Threading.Thread.Sleep(2000);

Thanks, Parth