Excel VBA: Speed up macro execution

Speed up macro execution by turning off screen updating/flicker.

'Turn Off Screen Updating
Application.ScreenUpdating = False
'Optional: Refresh/Update screen manually when needed
Application.ScreenRefresh

'Your Code

'Turn On Screen Updating
Application.ScreenUpdating = True

Excel VBA: Check for Comments

'If Comment does not exist
 If Range("B4").Comment Is Nothing Then
 Range("B4").Value = "Does not exist."
 End If

 'If Comment exist
 If Not Range("C4").Comment Is Nothing Then
 Range("C4").Value = Range("C4").Comment.Text
 End If