Prior to Microsoft Office 2013, all Excel windows opened in the same instance of Excel. This meant that workbooks were stacked behind each other, so you were not able to view two side-by-side in full monitor view.
This issue has been resolved in Office 2013 onwards, whereby each Excel file is opened in its own instance of Excel, allowing you to put them side-by-side, on two screens or in whichever situation you desired.
For users still using Office 2010 and older, the following macro will allow you to use an Open File Dialog box and force it to open in a new instance of Excel – without needing to load a new Excel first.
You can add this macro to your personal workbook, and then create a short cut to your quick access tool bar or a custom ribbon in order to use this in a one-click shortcut method.
Sub OpenInNewWindow() ' Written by: FormatCells.com ' For the best custom made spreadsheets, visit: www.formatcells.com Dim lngCount As Long Dim objExcel As Object, objWorkbook As Object Dim openPath As String, DefaultLoadPath As String DefaultLoadPath = "" 'AUTO LOAD DIALOG BOX INTO THIS PATH 'LOAD OPEN FILE DIALOG BOX With Application.FileDialog(msoFileDialogOpen) Application.FileDialog(msoFileDialogOpen).InitialFileName = DefaultLoadPath 'LOAD DEFAULT PATH, OR YOUR DOCUMENTS IF BLANK Application.FileDialog(msoFileDialogOpen).Title = "Open File in Seperate Excel" 'TITLE OF THE WINDOW Application.FileDialog(msoFileDialogOpen).Filters.Add "All Excel Files", "*.xlsx,*.xlsm" 'FILTER BY EXCEL FILES .AllowMultiSelect = False 'ONLY OPEN ONE FILE .Show 'EXIT IF NOTHING CHOSEN If .SelectedItems.Count < 1 Then Exit Sub End If 'TAKE THE PATH openPath = .SelectedItems(1) End With 'IF NO PATH WAS FED THROUGH, THEN EXIT If openPath = "" Then Exit Sub End If Application.StatusBar = "Loading " & openPath & "..." Set objExcel = CreateObject("Excel.Application") objExcel.Visible = True Set objWorkbook = objExcel.Workbooks.Open(openPath) Application.StatusBar = False End Sub