Hello, I need to open a log file, but the files always in use..

no matter what i do I keep getting

"An unhandled exception of type 'System.IO.IOException' occurred in mscorlib.dll

Additional information: The process cannot access the file "... .log" because it is being used by another process."

I can open the file in notepad and wordpad, why cant I / how do I open it in my code?

this is my code now.
[code=vb]
If IO.File.Exists(LogPath) = True Then
Dim st As IO.FileStream = IO.File.Open(LogPath, IO.FileMode.Open, IO.FileAccess.Read, IO.FileShare.Read)
Dim sr As New IO.StreamReader(st)
Dim a() As String = Split(sr.ReadToEnd, vbCrLf)
[/code]