Copy whole column from closed workbook into open workbook - excel

Question

I am trying to copy data from a closed workbook into an open workbook, setup is as follows:
Closed workbook (random filename, random sheet name) has data in single sheet, column A.
Open workbook needs to paste data into existing "data" sheet in the next available column
It seems very simple, but I have been having a hell of a time trying to get it to work, this is the best i can do below, but it returns with an out of range error.
Sub Test
Dim fileName As Variant
Dim tableName, hideRow As String
Dim sheetRange As Range
Dim i As Integer
Dim freecolumn As Integer
Dim newWorkbook As Workbook
Dim currentbook As String
'open dialogue box to get new file to import
fileName = Application.GetOpenFilename
' run update in background
'Application.ScreenUpdating = False
ThisWorkbook.Activate
Sheets("Data").Select
freecolumn = ActiveSheet.UsedRange.Columns.Count + 1
Set newWorkbook = Workbooks.Open(fileName, ReadOnly:=True)
' tried this method, but didnt work
'Workbooks(fileName).Worksheets(1).Range("A:A").Copy _
'Worksheets("Data").Range(freecolumn)
' also tried this
'Workbooks(fileName).Sheets(1).Columns(1).Copy Destination:=Workbooks(currentbook).Sheets("Data").Columns(freecolumn)
'Sheets("Data").Range(freecolumn).Resize(fileName.Rows.Count).Value = fileName.Value
'closedBook.Sheets(1).Copy After:=ThisWorkbook.Sheets(ThisWorkbook.Sheets.Count)
'closedBook.Close SaveChanges:=False
'Application.ScreenUpdating = True
End Sub

Answer 1

Is this what you are trying? I have commented the code but If you find any bugs or have any questions, feel free to leave a comment below.
CODE
Option Explicit
Sub Sample()
Dim Ret As Variant
Dim wbThis As Workbook, wbThat As Workbook
Dim wsThis As Worksheet, wsThat As Worksheet
Dim LastCol As Long
'~~> Set your current workbook
Set wbThis = ThisWorkbook
'~~> This is the sheet where you want to copy the data to
Set wsThis = wbThis.Sheets("Data")
'~~> Finding last column in data sheet
With wsThis
If Application.WorksheetFunction.CountA(.Cells) <> 0 Then
LastCol = .Cells.Find(What:="*", _
After:=.Range("A1"), _
Lookat:=xlPart, _
LookIn:=xlFormulas, _
SearchOrder:=xlByColumns, _
SearchDirection:=xlPrevious, _
MatchCase:=False).Column + 1
Else
LastCol = 1
End If
End With
'~~> Make user choose the file
Ret = Application.GetOpenFilename("Excel Files (*.xls*), *.xls*")
'~~> If user presses cancel
If Ret = False Then Exit Sub
'~~> Open workbook
Set wbThat = Workbooks.Open(Ret)
'~~> Work with sheet 1
Set wsThat = wbThat.Sheets(1)
'~~> Copy and paste the columns
wsThat.Columns(1).Copy wsThis.Columns(LastCol)
'~~> Close the file without saving
wbThat.Close (False)
End Sub
WORTH A READ
Avoid the use of .Select
Finding last row/column in a worksheet