[2005] VS.net 2005 BUG???

[Simply Me]

Hi! I wonder if this is a bug... I kept getting these errors from time to time but I cant single out what's causing it.

My proj runs on a network and this happens when the user will click a save button to save records in the database (data table). Is this a bug?? if not, can someone please help me out in fixing these errors?

Attached are the errors I get and if it will help. this is how I accessed my database as well as how I save the records.

Private Sub btnDisplay_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplay.Click
        SuspendLayout()
        cnn.ConnectionString = "Data Source=.\sqlexpress;Initial Catalog=MYDB;Integrated Security=True"
 
        If cnn.State = ConnectionState.Closed Then cnn.Open()
 
 
        cmdGrade = cnn.CreateCommand
        cmdGrade.CommandText = "SELECT DISTINCT * FROM tblEnrol WHERE SectionName = '" & cboSection.Text & "' AND SubjectName = '" & cboSubjectName.Text & "' AND YearLevel = '" & cboYearLevel.Text & "'"
        daGrade.MissingSchemaAction = MissingSchemaAction.AddWithKey
        dsGrade.Clear()
        'dsSection.Clear()
        'dsSubject.Clear()
        daGrade.SelectCommand = cmdGrade
        daGrade.Fill(dsGrade, "tblEnrol")
        cnn.Close()
 
 
 
        Dim si() As FarPoint.Win.Spread.SortInfo = New FarPoint.Win.Spread.SortInfo() {New FarPoint.Win.Spread.SortInfo(1, True), New FarPoint.Win.Spread.SortInfo(2, True)}
 
        ''HideSheets()
 
        'bind fpspread1 to datasource
        '1st Grading
        FpSpread1.Sheets(0).DataSource = dsGrade
        FpSpread1.Sheets(0).DataMember = "tblEnrol"
 
        'Create CellType and specify number decimal for 1st grading sheet
        With FpSpread1.Sheets(0)
            .DataAutoCellTypes = False
            Dim num As New FarPoint.Win.Spread.CellType.NumberCellType
            num.DecimalPlaces = 0
            .Columns(12, 81).CellType = num 'column 12 to 81
            .Columns(84, 85).CellType = num
            .Columns(88, 89).CellType = num
            .Columns(92, 93).CellType = num
            .Columns(96, 97).CellType = num
            .Columns(100, 101).CellType = num
            .Columns(104, 105).CellType = num
            .Columns(109).CellType = num
 
            'sort multi-column
            .SortRows(0, FpSpread1.Sheets(0).RowCount, si)
 
        End With
        FormatSpread()
 
        'bind FpSpread1.Sheets(1) to datasource
        '2nd Grading
        FpSpread1.Sheets(1).DataSource = dsGrade
        FpSpread1.Sheets(1).DataMember = "tblEnrol"
 
        'Create CellType and specify number decimal for 1st grading sheet
        With FpSpread1.Sheets(1)
            .DataAutoCellTypes = False
            Dim num As New FarPoint.Win.Spread.CellType.NumberCellType
            num.DecimalPlaces = 0
 
            'for 2nd grading cell type
            .Columns(135, 204).CellType = num 'Assignment to Total Score (A)
            .Columns(207, 208).CellType = num 'Total Quiz to Total Score (Q)
            .Columns(211, 212).CellType = num 'Total Rec to Total Score (R)
            .Columns(215, 216).CellType = num 'Total Proj to Total Score (P)
            .Columns(219, 220).CellType = num 'Total Speech to Total Score (SP)
            .Columns(223, 224).CellType = num 'Total Reading to Total Score (RDG)
            .Columns(227, 228).CellType = num 'Total Exam to Total Score (E)
            .Columns(232).CellType = num 'Average
        End With
        FormatSpread1()
End Sub

Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
        'SuspendLayout()
         dsGrade = CType(FpSpread1.ActiveSheet.DataSource, System.Data.DataSet)
 
        'Save the changes back to the database
        Try
            daGrade.Update(dsGrade.Tables("tblEnrol"))
            dsGrade.AcceptChanges()
            FormatSpread()
            FormatSpread1()
            formatspread2()
            FormatSpread3()
            formatspread4()
            FormatSpread5()
 
            formatspread7()
            formatspread11()
 
            MessageBox.Show("Changes are comitted to the database")
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try
 
        ' ResumeLayout()
    End Sub