Question

I’m trying to update an Excel file from Outlook (Office 2010). How do I reference and access Excel?

As a simple test I’m trying to count the number of open workbooks. When I run this I get 0, even though there are 2 open.

Sub Test()
    Dim xlApp As Excel.Application
    Dim xlWBook As Excel.Workbook

    Set xlApp = New Excel.Application
    Debug.Print "xlApp.Workbooks.Count = " & xlApp.Workbooks.Count

    On Error Resume Next
    Set xlWBook = xlApp.Workbooks("Data.xlsx")
    Err.Clear 'Clear error and open File Index

    If  xlWBook Is Nothing Then
        Set xlWBook = xlApp.Workbooks.Open("C:\Users\Chris\Desktop\Data.xlsx")
    End If
End Sub

Answer 1

This is what I use to detect Excel:

Dim xlApp As excel.Application
On Error Resume Next
Set xlApp = GetObject(, "Excel.Application")
If Err.Number = 429 Then 'Excel not running
    Set xlApp = CreateObject("Excel.Application")
End If
On Error GoTo 0

once xlApp is set, you can use xlApp.Workbooks.Count to count the worksheets

Note: This code will get the first one opened, if there are more than one instance of Excel to find

If you have to find a specific workbook, from this page, Set xlApp = GetObject("Book2").Application will find the workbook, even if it’s not in the first instance. If the workbook is from a file, or already saved, replace book2 with the full path and filename – Side effect – this will also open the file if it is not already open
More usage info: http://msdn.microsoft.com/en-us/library/aa164798%28v=office.10%29.aspx