Cannot read file from disk - vb.net

Question

When I upload an excel file from my vb app, it's fine for the first time. If I try it a second time I am having this error: The process cannot access the file (path) because it is bein used by another process. Below is my code:
Dim fd As OpenFileDialog = New OpenFileDialog()
fd.Title = "Open File Dialog"
fd.InitialDirectory = "C:\"
fd.Filter = "All files (*.xlsx)|*.xlsx|All files (*.xlsx)|*.xlsx"
fd.FilterIndex = 2
fd.RestoreDirectory = True
Dim myStream As Stream = Nothing
If fd.ShowDialog() = DialogResult.OK Then
Try
myStream = fd.OpenFile()
If (myStream IsNot Nothing) Then
workbook = APP.Workbooks.Open(fd.FileName)
worksheet = workbook.Worksheets("sheet1")
TextBox1.Text = worksheet.Cells(1, 7).Value
TextBox2.Text = worksheet.Cells(2, 7).Value
TextBox3.Text = worksheet.Cells(3, 7).Value
l1.Text = worksheet.Cells(2, 1).Value * 10
w1.Text = worksheet.Cells(2, 2).Value * 10
q1.Text = worksheet.Cells(2, 3).Value
p1.Text = worksheet.Cells(2, 4).Value..........
Dim Values(119, 3) As String
Values(0, 0) = l1.Text
Values(0, 1) = w1.Text
Values(0, 2) = q1.Text
Values(0, 3) = p1.Text.........
Dim add As Integer = 0
Dim pressing As Integer = 0
If adding.Text = "50" Or adding.Text = "" Then
add = 50
Else
add = Convert.ToInt16(adding.Text)
End If
If press.Text = "20" Or press.Text = "" Then
pressing = 20
Else
pressing = Convert.ToInt16(press.Text)
End If
Dim l As Integer
Dim w As Integer
Dim machinearea As Integer
Dim connetionString As String
Dim cnn As SqlConnection
connetionString = "Data Source=.;Initial Catalog=lumber;User ID=sa;Password=sasql"
cnn = New SqlConnection(connetionString)
Dim cmd As SqlCommand
Dim myreader As SqlDataReader
Dim query As String
query = "SELECT length,width from marea"
cmd = New SqlCommand(query, cnn)
cnn.Open()
myreader = cmd.ExecuteReader()
If myreader.Read() Then
l = myreader.Item("length")
w = myreader.Item("width")
End If
cnn.Close()
machinearea = l * w
Dim allTextBoxes2 = From txt In Me.Panel1.Controls.OfType(Of TextBox)()
Order By txt.TabIndex
Dim txtList2 = allTextBoxes2.ToList()
For i As Int32 = 0 To txtList2.Count - 1
Dim thisTxt = txtList2(i)
Dim nextIndex = If(i + 1 >= txtList2.Count, 0, i + 1)
Dim prevIndex = If(i - 1 < 0, txtList2.Count - 1, i - 1)
Dim nextTxt = txtList2(nextIndex)
Dim prevTxt = txtList2(prevIndex)
Dim testInt As Integer = 0
If thisTxt.Text = "0" Then
thisTxt.Clear()
End If
Next
Dim allTextBoxes = From txt In Me.Panel1.Controls.OfType(Of TextBox)()
Order By txt.TabIndex
Dim txtList = allTextBoxes.ToList()
For i As Int32 = 0 To txtList.Count - 1
Dim thisTxt = txtList(i)
For j = 2 To -1
For k = 1 To 4
thisTxt.Text = worksheet.Cells(i + j, k).Value
Next
Next
Next
End If
Catch Ex As Exception
MessageBox.Show("Cannot read file from disk. Original error: " & Ex.Message)
Finally
' Check this again, since we need to make sure we didn't throw an exception on open.
If (myStream IsNot Nothing) Then
myStream.Close()
End If
End Try
End If

Answer 1

Try
myStream = fd.OpenFile()
If (myStream IsNot Nothing) Then
workbook = APP.Workbooks.Open(fd.FileName, ReadOnly:=True, Notify:=False)
worksheet = workbook.Worksheets("sheet1")
...
Finally
' Check this again, since we need to make sure we didn't throw an exception on open.
If (myStream IsNot Nothing) Then
myStream.Close()
End If
If (workbook IsNot Nothing) Then
workbook.Close()
End If
End Try

Answer 2

Make sure the application is closed and no process is running or it will give you that error.