Can't launch .exe - vb.net

Question

Trying to make a "world of warcraft" launcher.
How it should work:
When you press " Start Authserver " you get to locate the authserver.exe. the location is then saved so you don't have to do that twice.
Once pressed, it obviously should launch the authserver.exe.
What happens:
When you press " Start Authserver " it opens and instantly closes with error:
Error, couldn't open cause authserver.conf couldn't be located.
Notice:
Authserver.exe and authserver.conf is in the same folder, I'm able to launch it manually.
Mort helped me with similar problem yesterday, i hoped that the same VB code would work since that would seem obvious.
Private filePath As String = String.Empty
Private Sub PlayButton_Click(sender As System.Object, e As System.EventArgs) Handles PlayButton.Click
Try
If filePath.Length = 0 Then
Dim diagResult As DialogResult = OpenFileDialog1.ShowDialog()
If diagResult = Windows.Forms.DialogResult.OK Then
filePath = OpenFileDialog1.FileName
If filePath.ToUpper.EndsWith("WOW.EXE") Then
Process.Start(filePath)
Else
MessageBox.Show("Wrong file selected!")
filePath = String.Empty
End If
End If
Else
Process.Start(filePath)
End If
Catch ex As Exception
MessageBox.Show(String.Concat("An error occurred in the play button click:", ex.Message))
End Try
End Sub
Anyone got an idea?
In advance: Thanks.

Answer 1

Try something like this:
Private Sub PlayButton_Click(sender As System.Object, e As System.EventArgs) Handles PlayButton.Click
Try
OpenFileDialog1.FileName = ""
OpenFileDialog1.Filter = "World of Warcraft (WOW.EXE)|WOW.EXE"
Dim diagResult As DialogResult = OpenFileDialog1.ShowDialog
If diagResult = Windows.Forms.DialogResult.OK Then
Dim p As New Process
Dim fn As New System.IO.FileInfo(OpenFileDialog1.FileName)
p.StartInfo.WorkingDirectory = fn.DirectoryName
p.StartInfo.FileName = fn.Name
p.Start()
End If
Catch ex As Exception
MessageBox.Show(String.Concat("An error occurred in the play button click:", ex.Message))
End Try
End Sub