Filename with filenumbers

[AceInfinity]

Private Sub SaveToText()
 
        Dim num As Integer
        Dim filenumber As Integer
 
        Dim s As Short
        Dim newstr(6) As String
 
        Dim I As Integer
 
        Dim Name As String
        Dim Label As String
        Dim AvailSpace As String
        Dim TSize As String
        Dim DriveFormat As String
        Dim DriveReady As String
 
        Dim ItemCount As Integer
        ItemCount = Me.ListView1.Items.Count
 
        If (Not System.IO.Directory.Exists("Drive Data")) Then
            System.IO.Directory.CreateDirectory("Drive Data")
        End If
 
        If File.Exists("DriveData\driveinfo" & num & ".txt") Then
            While File.Exists("DriveData\driveinfo" & num & ".txt")
                num = num + 1
            End While
            filenumber = num
        Else
            filenumber = 1
        End If
 
        Dim outputstream As New IO.StreamWriter("Drive Data\driveinfo" & filenumber & ".txt")
 
        For I = 0 To ItemCount - 1
 
            For s = 0 To 5
                newstr(s) = ListView1.Items.Item(I).SubItems(s).Text
            Next
 
            Name = newstr(0)
            Label = newstr(1)
            AvailSpace = newstr(2)
            TSize = newstr(3)
            DriveFormat = newstr(4)
            DriveReady = newstr(5)
 
            outputstream.WriteLine("Drive: " & Name.Trim() & " - " & Label.Trim() & " (Ready: " & DriveReady.Trim() & ")")
            outputstream.WriteLine("Available Space: " & AvailSpace.Trim())
            outputstream.WriteLine("Total Capacity: " & TSize.Trim())
            outputstream.WriteLine("Format: " & DriveFormat.Trim())
            outputstream.WriteLine("")
 
        Next I
 
        outputstream.Close()
 
        MsgBox(filenumber)
        MsgBox("Export has been successfully created!", MsgBoxStyle.Information, "Information")
 
    End Sub

Here's my code, and I can get it to create the directory "Drive Data" if it doesn't exist, and a file gets created as "driveinfo1.txt" but if that file exists it won't save the new file as "driveinfo2.txt" which is what i'm trying to get this code to do.

If anyone can help me understand where the logic in this is wrong and put me on the right path i'd appreciate that. Don't need someone to write the code for me, but i'm sure i'm just doing some silly mistake in this code not allowing it to work the way I want it to.