Проверка наличия файла

Imports Excel = Microsoft.Office.Interop.Excel
Public Class Form1
    Dim app As Excel.Application = CreateObject("Excel.Application")
    Dim book As Excel.Workbook = app.Workbooks.Open(Application.StartupPath & "\Book.xlsx")
    Dim sh As Excel.Worksheet = book.Worksheets("Лист1")
    Dim r As Long = sh.UsedRange.Rows.Count
    Dim Poisk(r, 10) As String
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
       Dim x As Long
        For x = 1 To r
            Poisk(x - 1, 1) = sh.Range("A" & x).Value
            Poisk(x - 1, 2) = sh.Range("B" & x).Value
            Poisk(x - 1, 3) = sh.Range("C" & x).Value
            Poisk(x - 1, 4) = sh.Range("D" & x).Value
            Poisk(x - 1, 5) = sh.Range("E" & x).Value
            Poisk(x - 1, 6) = sh.Range("F" & x).Value
            Poisk(x - 1, 7) = sh.Range("G" & x).Value
            Poisk(x - 1, 8) = sh.Range("H" & x).Value
            Poisk(x - 1, 9) = sh.Range("I" & x).Value
            Poisk(x - 1, 10) = sh.Range("J" & x).Value
        Next
      book.Close()
      app.Quit(
    End Sub
End Class

MsgBox(IO.File.Exists("Path"))

Imports Excel = Microsoft.Office.Interop.Excel
Public Class Form1
    Dim app As Excel.Application = CreateObject("Excel.Application")
    Dim book As Excel.Workbook = app.Workbooks.Open(Application.StartupPath & "\Book.xlsx")
    Dim sh As Excel.Worksheet = book.Worksheets("Лист1")
    Dim r As Long = sh.UsedRange.Rows.Count
    Dim Poisk(r, 10) As String
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    End Sub
End Class

 
    Dim app As Excel.Application = CreateObject("Excel.Application")
    Dim book As Excel.Workbook = app.Workbooks.Open(Application.StartupPath & "\Book.xlsx")
    Dim sh As Excel.Worksheet = book.Worksheets("Лист1")
    Dim r As Long = sh.UsedRange.Rows.Count
    Dim Poisk(r, 10) As String

If IO.File.Exists("Путь") Then
'Действие
Else
MsgBox("Файла нет!")
End If

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
If Not IO.File.Exists("Путь") Then ' Проверка файла
IO.File.Create("Путь") 'Если нет, то создать
End If
    End Sub

Imports System.IO

    Dim app As Excel.Application 
    Dim book As Excel.Workbook 
.....

app = CreateObject("Excel.Application")
'Проверка файла, и если есть, то
book = app.Workbooks.Open(Application.StartupPath & "\Book.xlsx")

Dim app As Excel.Application = CreateObject("Excel.Application")
* * Dim book As Excel.Workbook = app.Workbooks.Open(Application.StartupPath & "\Book.xlsx")
* * Dim sh As Excel.Worksheet = book.Worksheets("Лист1")
* * Dim r As Long = sh.UsedRange.Rows.Count
* * Dim Poisk(r, 10) As String

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim i As MsgBoxResult
        If Not IO.File.Exists(Application.StartupPath & "\Book.xlsx") Then
            i = MsgBox("Файл не найден!" & vbCrLf & "Создать новый файл?", MsgBoxStyle.OkCancel, "Отсутствует файл")
            If i = MsgBoxResult.Ok Then
                app = New Excel.Application
                book = app.Workbooks.Add
                sh = book.Sheets("Лист1")
                book.SaveAs(Application.StartupPath & "\Book.xlsx")
                book.Close()
                app.Quit()
            Else
                MsgBox("Работа программы невозможна!" & vbCrLf & "Отсутствует файл!", MsgBoxStyle.Critical, "Завершение")
                Me.Close()
                Exit Sub
            End If
        End If
End Sub