[RESOLVED] [2005] Being used by another process error

The problem seems to be with a text file that I'm accessing. I can't figure out where the problem might be. From the code i'm getting errors at
Error Place 4 and 5 (you will see what i mean by that below). The message says that the file

(Application.StartupPath & "\UserHistory.txt")

is being used by another process but I've checked and this is the only code that can access the text file in question. Anyone spot what's the
matter with it? Here's the relevant code:

VB Code:

Try
            If System.IO.File.Exists(Application.StartupPath & "\UserHistory.txt") = False Then
                System.IO.File.Create(Application.StartupPath & "\UserHistory.txt") 'CREATE FILE
            End If     'DO I NEED TO RELEASE THE FILE OR SOMETHING??
        Catch ex As Exception
            MessageBox.Show(ex.Message & "ERROR PLACE 1")
        End Try
 
'THERE'S CODE HERE TO CHECK THAT ALL FIELDS HAVE BEEN FILLED IN
'THEN...
 
'Once TRUE create User Account
        'FIRST CREATE USER FOLDER:
        'DEFINE THE USER FOLDER PATH TO CHECK/CREATE
        Dim userPath As String = Application.StartupPath & "\User Accounts\" & _
        txtSurname.Text.ToLower & "\" & txtCreateUsername.Text.ToLower & "\"
 
        Try
            If Not My.Computer.FileSystem.DirectoryExists(userPath) Then
                'CREATE FOLDER
               My.Computer.FileSystem.CreateDirectory(userPath)
            ElseIf My.Computer.FileSystem.DirectoryExists(userPath) Then
                'Check Sub Directory Text File
                MessageBox.Show("An account with these details already exists." & _
                "Please select a new username or use the account details finder to" & _
                "get your existing details", "Account already exists", MessageBoxButtons.OK)
                txtCreateUsername.Clear()    'Clear & reselect 
                txtCreateUsername.Select()   'username field
                Exit Sub
            End If
        Catch ex As Exception
            MessageBox.Show(ex.Message & "ERROR PLACE 2")
        End Try
 
        'Once check has been made, create a text file that 
        'will contain all the  user details:
        Try
            'Create STREAMWRITER
            Dim sw As New System.IO.StreamWriter(userPath & "\userDetails.txt")
            Dim UserDOB As Date = CDate(cboDay.Text & "/" & cboMonth.Text & "/" & cboYear.Text)
            sw.Write("Surname:" & txtSurname.Text.ToLower & Environment.NewLine)
            sw.Write("First Name:" & txtFirstName.Text.ToLower & Environment.NewLine)
            sw.Write("Occupation:" & cboOccupation.Text.ToLower & Environment.NewLine)
            sw.Write("DOB:" & UserDOB & Environment.NewLine)
            sw.Write("Username:" & txtCreateUsername.Text.ToLower & Environment.NewLine)
            sw.Write("Password:" & txtCreatePassword.Text.ToLower & Environment.NewLine)
            sw.Write("Question:" & cboPWquestion.SelectedItem.ToString & Environment.NewLine) 'SELECTED SECURITY QUESTION
            sw.Write("Answer:" & txtPWAnswer.Text.ToLower & Environment.NewLine) 'ANSWER TO SECURITY QUESTION
            sw.Close()        'CLOSE & DISPOSE OF STREAMWRITER
            sw.Dispose()
        Catch ex As Exception
            MessageBox.Show(ex.Message & "ERROR PLACE 3")
        End Try
 
        'ADD CUURENT USER SURNAME TO A LOG FILE OF SURNAMES: 
        'BEFORE ADDING, CHECK FOR DUPLICATE 
        Try
            'FIRSTLY, READ EXISTING NAMES FROM LOG FILE 
            Dim srNew As New System.IO.StreamReader(Application.StartupPath & "\UserHistory.txt")
            If srNew.Peek = -1 Then Exit Try 'Check if text file has text in it
            Do While srNew.Peek <> -1
                arr.Add(srNew.ReadLine)
            Loop
            srNew.Close()
            srNew.Dispose()
            arr.Sort()
        Catch ex As Exception
            MessageBox.Show(ex.Message & "ERROR PLACE 4")
        End Try
 
        Try   'NOW CHECK AGAINST TEXT ENTERED INTO SURNAME FIELD
            For Each item As String In arr
                If txtSurname.Text.ToLower = item Then
                    MessageBox.Show("Surname already exists.")
                    Exit Try
                End If
            Next
            My.Computer.FileSystem.WriteAllText(Application.StartupPath & "\UserHistory.txt", _
          Environment.NewLine & txtSurname.Text.ToLower, True)
        Catch ex As Exception
            MessageBox.Show(ex.Message & "ERROR PLACE 5")
        End Try
 
        MessageBox.Show("Congratulations! Account created successfully! You can now log on.", "Account Created", MessageBoxButtons.OK)
        Me.grPersonal.Visible = False
        Me.grpPassword.Visible = False
        pnlLogin.Show()
        Call FillUserHistory()

I think when you create the file up top, it is actually a function that returns some sort of stream. You should assign it to a variable and then close it.

I'm pretty sure that's where the problem lies.

I have gone through every line and when the file exists there isn't a problem. I had made a comment in the code about releasing the file after it's created as a possible reason(or whatever the term is). I think that's the case.

Specifying the filename as a String variable doesn't seem to fix the problem though.

EDIT - I moved the code to the form_Load event (instead of within button click) and it seems to work okay. At this stage, that will do for me! I'll mark it resolved but if anyone can explain how to fix this properly then please feel free to reply.

Stim

File.Create(filePath) doesn't just create the file but also opens it to return a filestream. So if you just want to create the file without writing anything to it then you must close the filestream to release that file for later use.
Your code should be changed to:

VB Code:

If System.IO.File.Exists(Application.StartupPath & "\UserHistory.txt") = False Then
                System.IO.File.Create(Application.StartupPath & "\UserHistory.txt").Close() 'CREATE FILE THEN CLOSE IT
            End If

Ahh, that's what I've been looking for.

I was wondering how to close the stream. Usually with Streamreader for example you can just do something like sr.close

I didn't know you could just add .Close to the end of File.Create(filehere)

Live and learn.

Thanks,

Stim.