deleting empty rows

Hi,

I need to write a macro which checks cells in one column and if the cell is empty it deletes the whole row (which contains the cell).

I tried this code but it doesn't delete all rows with empty cells:

Public Sub deleterows()
For o = 7 To 25
     If Worksheets("sheet").Cells(o, 4) = "" Then
        Rows(o).Delete
        End If
     End If
Next o
End Sub

So I modified the code:

Public Sub deleterows()
For o = 7 To 25
     If Worksheets("sheet").Cells(o, 4) = "" Then
        Rows(o).Delete
         o = o - 1
         a = a + 1
         If a = 20 Then
             o = 25
         End If
     End If
Next o
End Sub

It works correct but it is not a proper solution (it ends the for loop after 20 deleted cells)...

Do you have any better suggestions?

Thanks!