Windows service on system startup behaves differently - sql-server

Question

I have a Windows service which inserts into a database whenever there is a change in data from an OPC Server(KepServer). The service inserts correctly when I manually start it from the Services Task Manager of Windows 7. But the service only inserts one row of data when starting up on system startup, whereas the desired number of rows must be 20. Because it is Windows Service, it is difficult to debug and it is not giving any error as well.
jjag
OS:Windows 7;
DB:SQL Server Express;
Win Service:run under Administrator
My code:
Protected Overrides Sub OnStart(ByVal args() As String)
' Add code here to start your service.
'Create a new OPC Server object
ConnectedOPCServer = New OPCServer
ConnectedOPCServer.Connect("KEPware.KEPServerEx.V5")
Try
' Add the group and set its update rate
ConnectedServerGroups = ConnectedOPCServer.OPCGroups
ConnectedGroup = ConnectedServerGroups.Add("Test1")
Catch ex As Exception
' Error handling
End Try
' Set the update rate for the group
ConnectedGroup.UpdateRate = 400
' Subscribe the group so that you will be able to get the data change
' callbacks from the server
ConnectedGroup.IsSubscribed = True
ItemCount = 3
OPCItemIDs(1) = "Channel2.Device1.EndDate"
OPCItemIDs(2) = "Channel2.Device1.Material"
OPCItemIDs(3) = "Channel2.Device1.BatchSchedule"
ClientHandles(1) = 1
ClientHandles(2) = 2
ClientHandles(3) = 3
Try
' Establish a connection to the OPC item interface of the connected group
OPCItemCollection = ConnectedGroup.OPCItems
OPCItemCollection.DefaultIsActive = True
OPCItemCollection.AddItems(ItemCount, OPCItemIDs, ClientHandles, ItemServerHandles, ItemServerErrors)
Catch ex As Exception
' Error handling
End Try
EventLog1.WriteEntry("In OnStart")
End Sub
Public Sub ConnectedGroup_DataChange(ByVal TransactionID As Integer, ByVal NumItems As Integer, ByRef ClientHandles As System.Array, ByRef ItemValues As System.Array, ByRef Qualities As System.Array, ByRef TimeStamps As System.Array) Handles ConnectedGroup.DataChange
'This is my sub which inserts into database in the event of data change from OPC Server
Const NoOfItems = 3
Dim ObjOPCItem As OPCAutomation.OPCItem
Dim Array_Values(NoOfItems) As Object
For Each ObjOPCItem In OPCItemCollection
Array_Values(ObjOPCItem.ClientHandle) = ObjOPCItem.Value
Next
ObjOPCItem = Nothing
Dim sql As String
sql = "INSERT INTO BatchReport (BatchCode,BatchNumber)VALUES(#AV,#AVa);"
If Array_Values(3) < 20 Then
Try
connection.Open()
dataadapter.InsertCommand = New SqlCommand(sql, connection)
dataadapter.InsertCommand.Parameters.Add("#AV", SqlDbType.Int, 4).Value = Array_Values(1)
dataadapter.InsertCommand.Parameters.Add("#AVa", SqlDbType.Int, 4).Value = Array_Values(3)
dataadapter.InsertCommand.ExecuteNonQuery()
Catch ex As Exception
MsgBox(ex.ToString)
End Try
connection.Close()
End If
End Sub