My first code was just an example showing how to call the Replace function to replace the characters to get rid of the square boxes; you need to call it in a loop for each cell. Also it looks like the square boxes are caused by just Chr(13), and Excel needs these to be replaced by Chr(10) to give a new line in a cell.
Sub vbax()
Dim LR As Long, r As Long
With Sheets("Sheet1")
LR = .Cells(.Rows.Count, "A").End(xlUp).Row
For r = 2 To LR
.Cells(r, "C").Value = Replace(.Cells(r, "A").Value, Chr(13), Chr(10))
Next
End With
End Sub
I used the following code to determine which characters were present in the cells.
Sub Show_Chars()
Dim i As Integer, s As String
s = Cells(2, "A").Value
Debug.Print s
For i = 1 To Len(s)
Debug.Print Mid(s, i, 1), Asc(Mid(s, i, 1))
Next
End Sub