PULL的错误怎么解决

Private Sub MyPull(ByVal MyTable As String)'ExistTable表中存放PPC本地数据库的所有表格名称，MyTable为要PULL的表格
        Dim rdaNW As New SqlCeRemoteDataAccess
        Dim dbEngine As New SqlCeEngine
        Dim connDB As New SqlCeConnection(strConnLocal)
        Dim cmndDB As New SqlCeCommand("SELECT * FROM ExistTable WHERE TableName='" + MyTable + "'", connDB)
        Dim drdrDB As SqlCeDataReader
        '判断本地数据库是否存在该表
        connDB.Open()
        drdrDB = cmndDB.ExecuteReader()
        If drdrDB.Read = False Then
            MsgBox("该表不存在")'表格不存在，则先在MyTable里插入该表名，然后PULL
            With cmndDB
                .CommandText = "INSERT ExistTable(TableName) VALUES('" + MyTable + "')"
                .ExecuteNonQuery()
            End With
        Else
            MsgBox("表格存在！")'表格存在，则先删除本地表，然后PULL
            With cmndDB
                .CommandText = "DROP TABLE " + MyTable
                .ExecuteNonQuery()
            End With
        End If
        connDB.Close()
        Try
            With rdaNW
                .LocalConnectionString = strConnLocal
                .InternetUrl = strURL
                .InternetLogin = ""
                .InternetPassword = ""
                .Pull(MyTable, strSQL, strConnRemote, RdaTrackOption.TrackingOn)
            End With
            MsgBox("Pull OK!")
        Catch exSQL As Exception
            MsgBox(exSQL.Message)
        Finally
            rdaNW.Dispose()
        End Try
    End Sub