I am learning to create menu buttons and use the perform click. When I began by using the about in my code it works fine. However, when I try to do a perform click wiht my exit button in the menu strip it does not do anything...

Public Class Form1

    'Module level variables - These are private because they do 
    'Const for Retirement
    Const RETIREMENT_STANDARD As Decimal = 0.05D
    Const RETIREMENT_401A As Decimal = 0.08D
    Private retirementRateDecimal As Decimal

    Private Sub computeButton_Click(sender As Object, e As EventArgs) Handles computeButton.Click
            'CONST VARIABLES NEVER CHANGE ----- REMEMBER THIS!!!!!!!!!!!!!!!!!!!!!!
            'Const for Insurance - These are not module level variables because the results can change after being added together
            Const MEDICAL_INSURANCE As Decimal = 35.75D
            Const LIFE_INSURANCE As Decimal = 18.35D
            Const DENTAL_INSURANCE As Decimal = 4D

            'Const for Federal Tax Rate decimals
            Const TAX_08_LEVEL As Decimal = 0.08D
            Const TAX_18_LEVEL As Decimal = 0.18D
            Const TAX_28_LEVEL As Decimal = 0.28D
            Const TAX_08_PERCENT As Decimal = 985D
            Const TAX_18_PERCENT As Decimal = 2450D

            'Declare variables
            Dim hoursDecimal, payRateDecimal, grossPayDecimal, benefitsDecimal, netPayDecimal, federalTaxDecimal As Decimal

            'Make sure textboxes are valid
            If nameTextBox.Text.Trim = String.Empty Then
                MessageBox.Show("Name is required", "Name Missing Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            ElseIf employeeIDMaskedTextBox.MaskCompleted = False Then
                MessageBox.Show("Employee ID is not complete", "Employee ID Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            ElseIf departmentTextBox.Text.Trim = String.Empty Then
                MessageBox.Show("Department is required", "Department Missing Error", MessageBoxButtons.OK, MessageBoxIcon.Error)

                'This means if the result in this textbox is not a number or is less than 0 or greater than 60 to return an error
            ElseIf IsNumeric(hoursWorkedTextBox.Text) = False Or Decimal.Parse(hoursWorkedTextBox.Text,
            Globalization.NumberStyles.Number) <= 0D Or Decimal.Parse(hoursWorkedTextBox.Text, Globalization.NumberStyles.Number) > 60D Then
                MessageBox.Show("Hours worked must be a number between 0 and 60", "Hours Value Error", MessageBoxButtons.OK,
                'This means is the result in this textbox is not a number or less than 0 to return an error
            ElseIf IsNumeric(payRateTextBox.Text) = False Or Decimal.Parse(payRateTextBox.Text, Globalization.NumberStyles.Currency) <= 0D Then
                MessageBox.Show("Pay rate worked must be a number greater than zero", "Pay Rate Value Error", MessageBoxButtons.OK, MessageBoxIcon.Error)

                'Data rules are valid - Parse the textboxes
                hoursDecimal = Decimal.Parse(hoursWorkedTextBox.Text, Globalization.NumberStyles.Number)
                payRateDecimal = Decimal.Parse(payRateTextBox.Text, Globalization.NumberStyles.Currency)

                'Compute gross pay
                If hoursDecimal <= 40D Then
                    grossPayDecimal = Decimal.Round(hoursDecimal * payRateDecimal, 2)
                    grossPayDecimal = Decimal.Round((40D * payRateDecimal) + ((hoursDecimal - 40D) * payRateDecimal * 1.5D), 2)
                End If

                'Compute insurance benefit deduction
                If medicalInsuranceCheckBox.Checked Then
                    benefitsDecimal += MEDICAL_INSURANCE
                End If
                If lifeInsuranceCheckBox.Checked Then
                    benefitsDecimal += LIFE_INSURANCE
                End If
                If dentalInsuranceCheckBox.Checked Then
                    benefitsDecimal += DENTAL_INSURANCE
                End If

                'Compute the federal tax
                'Use this when a single variable, single expression, single control property, or similiar object
                'is to be evaluated and different actions are taken depending on the value of the expression
                'Advantage is it is easier to read than multiple if statements
                Select Case grossPayDecimal
                    Case Is <= TAX_08_PERCENT
                        federalTaxDecimal = Decimal.Round(TAX_08_LEVEL * grossPayDecimal, 2)
                    Case Is <= TAX_18_PERCENT
                        federalTaxDecimal = Decimal.Round(grossPayDecimal * TAX_18_LEVEL, 2)
                    Case Else
                        federalTaxDecimal = Decimal.Round(grossPayDecimal * TAX_28_LEVEL, 2)
                End Select

                'Use the retirement rate set in the checked changed event for the retirement radio button controls
                benefitsDecimal += Decimal.Round(grossPayDecimal * retirementRateDecimal, 2)

                'Compute the net pay
                netPayDecimal = grossPayDecimal - federalTaxDecimal - benefitsDecimal

                'Display output
                payRateTextBox.Text = payRateDecimal.ToString("C")
                grossPayTextBox.Text = grossPayDecimal.ToString("C")
                netPayTextBox.Text = netPayDecimal.ToString("C")
                federalTaxTextBox.Text = federalTaxDecimal.ToString("N")
                benefitsTextBox.Text = benefitsDecimal.ToString("N")

            End If
        Catch ex As Exception
            MessageBox.Show("Unexpected error: " & ControlChars.NewLine & ex.Message, "Compute Button Error",
                            MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try

    End Sub

    Private Sub exitButton_Click(sender As Object, e As EventArgs) Handles exitButton.Click
        'Close the form if the system user responds yes
        Dim messageString As String = "Do you want to close the form?"
        Dim buttonDialogResult As DialogResult = MessageBox.Show(messageString, "Quit?", MessageBoxButtons.YesNo, MessageBoxIcon.Question,
        If buttonDialogResult = Windows.Forms.DialogResult.Yes Then
        End If
    End Sub

    Private Sub resetButton_Click(sender As Object, e As EventArgs) Handles resetButton.Click
        'Reset all textboxcontrol

        'Reset retirement benefit status to none
        noRetirementPlanRadioButton.Checked = True

        'Uncheck benefits checkboxes
        medicalInsuranceCheckBox.Checked = False
        lifeInsuranceCheckBox.Checked = False
        dentalInsuranceCheckBox.Checked = False

        'Set focus to name textbox
    End Sub

    Private Sub noneRetirementPlanRadioButton_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles noRetirementPlanRadioButton.CheckedChanged,
        retirementStandardRadioButton.CheckedChanged, retirement401ARadioButton.CheckedChanged
        'Create a radio button in memory and store the values of sender to it
        Dim checkedRadioButton As RadioButton = CType(sender, RadioButton)

        'Use select case to evaluate the name of the radio button to decide which controls to enable/disable
        Select Case checkedRadioButton.Name
            Case "noRetirementRadioButton"
                retirementRateDecimal = 0D
            Case "retirementStandardRadioButton"
                retirementRateDecimal = RETIREMENT_STANDARD
            Case "retirement401ARadioButton"
                retirementRateDecimal = RETIREMENT_401A
        End Select
    End Sub

    Private Sub FileToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles FileToolStripMenuItem.Click

    End Sub

    Private Sub AboutToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles AboutToolStripMenuItem.Click
        'Display the About Message box
        Dim messageString As String = "Programmed by Bryan Kruep" & ControlChars.NewLine & "Today's Date/Time:  " & Date.Now.ToString
        Dim titleString As String = "About the Payroll Application"

        'Display output message
        MessageBox.Show(messageString, titleString, MessageBoxButtons.OK, MessageBoxIcon.Information)
    End Sub

    Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ExitToolStripMenuItem.Click
    End Sub
End Class