Отказано в доступе по пути при копировании файла

IO.File.Copy()

IO.File.Copy(Me.dgv_PlaylistCtl.Rows(i).Cells(3).Value, frm_Params.TargetFolderPath & "\" & Number & "_" & Me.dgv_PlaylistCtl.Rows(i).Cells(1).Value)

Private Sub btn_Do_Click(sender As Object, e As EventArgs) Handles btn_Do.Click
        If IO.Directory.Exists(frm_Params.TargetFolderPath) = True And frm_Params.Limit = False And frm_Params.InjectFiles = False Then
            If BackgroundWorker.IsBusy <> True Then
                Me.btn_Cancel.Enabled = True
                MsgBox(frm_Params.TargetFolderPath)
                BackgroundWorker.RunWorkerAsync()
            End If
        End If
    End Sub

Private Sub BackgroundWorker_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker.DoWork
        Dim Worker As System.ComponentModel.BackgroundWorker = CType(sender, System.ComponentModel.BackgroundWorker)
        Dim Number As Integer = 100
        Dim AllRows As Integer = Me.dgv_PlaylistCtl.RowCount
        Dim ProgressStep As Integer = 100 \ AllRows
        Dim Ostatok As Integer = 100 Mod AllRows
        Me.ProgressBar.Value = 0
        For i As Integer = 0 To AllRows - 1 Step 1
            If (Worker.CancellationPending = True) Then
                e.Cancel = True
                Exit For
            Else
                MsgBox(frm_Params.TargetFolderPath & "\" & Number & "_" & Me.dgv_PlaylistCtl.Rows(i).Cells(1).Value)
                Number = Number + 1
                Worker.ReportProgress(Me.ProgressBar.Value + ProgressStep)
                If 100 - Me.ProgressBar.Value = Ostatok Then Worker.ReportProgress(100)
            End If
        Next i
    End Sub

Private Sub BackgroundWorker_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker.DoWork
        Dim Worker As System.ComponentModel.BackgroundWorker = CType(sender, System.ComponentModel.BackgroundWorker)
        Dim Number As Integer = 100
        Dim AllRows As Integer = Me.dgv_PlaylistCtl.RowCount
        Dim ProgressStep As Integer = 100 \ AllRows
        Dim Ostatok As Integer = 100 Mod AllRows
        Me.ProgressBar.Value = 0
        For i As Integer = 0 To AllRows - 1 Step 1
            If (Worker.CancellationPending = True) Then
                e.Cancel = True
                Exit For
            Else
                Me.RichTextBox1.Text = frm_Params.TargetFolderPath & "\" & Number & "_" & Me.dgv_PlaylistCtl.Rows(i).Cells(1).Value
                Number = Number + 1
                Worker.ReportProgress(Me.ProgressBar.Value + ProgressStep)
                If 100 - Me.ProgressBar.Value = Ostatok Then Worker.ReportProgress(100)
            End If
        Next i
    End Sub

    Dim S As String = "Str"
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        DataGridView1.Rows.Add()
        DataGridView1(0, 0).Value = "Value"
        BackgroundWorker1.RunWorkerAsync()
    End Sub
 
    Private Sub BackgroundWorker1_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
        For I As Integer = 0 To 100
            Me.Text = S & " " & RichTextBox1.Text & " " & DataGridView1(0, 0).Value & " |" & I
            System.Threading.Thread.Sleep(300)
        Next
    End Sub

Imports System.IO
Imports System.ComponentModel
 
Private Sub btn_Do_Click(sender As Object, e As EventArgs) Handles btn_Do.Click
    If Directory.Exists(frm_Params.TargetFolderPath) AndAlso Not frm_Params.Limit AndAlso Not frm_Params.InjectFiles Then
        If Not BackgroundWorker.IsBusy Then
            Me.btn_Cancel.Enabled = True
            BackgroundWorker.RunWorkerAsync(frm_Params.TargetFolderPath)
        End If
    End If
End Sub
 
Private Sub BackgroundWorker_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker.DoWork
    Dim Worker As BackgroundWorker = DirectCast(sender, BackgroundWorker)
    Dim TargetFolderPath As String = DirectCast(e.Argument, String)
    
    ' Дальше без изменений. Только работаем с локальной переменной TargetFolderPath вместо frm_Params.TargetFolderPath
End Sub

Dim TargetFolderPath As String = DirectCast(e.Argument, String)