Copy Cell to another sheet in condition is met Loop - excel

Question

I need to loop through a column and if a conditions if met copy cell from one sheet to another.
I'm finding problems with the incremental..
In this case double the results.
Thank you in advance.
KR
Sub copycell()
Dim iLastRow As Long
Dim i As Long
Dim erow As Long
erow = 1
iLastRow = Worksheets("Clientes").Cells(Rows.Count, "C").End(xlUp).Row
For i = 13 To iLastRow
If Sheets("Clientes").Cells(i, 3) = "0" Then
Worksheets("Ficheros").Range("B" & erow).End(xlUp).Offset(1) = Sheets("Clientes").Cells(i, 4)
erow = erow + 1
End If
Next i
End Sub

Answer 1

Why not use Autofilter to filter the column C and if the autofilter returns any rows, copy them to the destination sheet?
See if something like this works for you...
Sub CopyCells()
Dim wsData As Worksheet, WsDest As Worksheet
Dim iLastRow As Long
Application.ScreenUpdating = False
Set wsData = Worksheets("Clientes")
Set WsDest = Worksheets("Ficheros")
iLastRow = wsData.Cells(Rows.Count, "C").End(xlUp).Row
wsData.AutoFilterMode = False
With wsData.Rows(12)
.AutoFilter field:=3, Criteria1:="0"
If wsData.Range("D12:D" & iLastRow).SpecialCells(xlCellTypeVisible).Cells.Count > 1 Then
wsData.Range("D13:D" & iLastRow).SpecialCells(xlCellTypeVisible).Copy
WsDest.Range("B" & Rows.Count).End(3)(2).PasteSpecial xlPasteValues
End If
End With
wsData.AutoFilterMode = False
Application.CutCopyMode = 0
Application.ScreenUpdating = True
End Sub

Answer 2

You can achieve your result with AutoFilter, but my answer is trying to resolve your code using the For loop.
Modified Code
Option Explicit
Sub copycell()
Dim iLastRow As Long
Dim i As Long
Dim erow As Long
' get first empty row in column B in "Ficheros" sheet
erow = Worksheets("Ficheros").Range("B" & Rows.Count).End(xlUp).Row + 1
With Worksheets("Clientes")
iLastRow = .Cells(.Rows.Count, "C").End(xlUp).Row
For i = 13 To iLastRow
If .Cells(i, 3) = "0" Then
Worksheets("Ficheros").Range("B" & erow) = .Cells(i, 4)
erow = erow + 1
End If
Next i
End With
End Sub