VB6/VBA Do not Allow COM Add-In to load

Question

I have a VB6/VBA application that hooks into Excel and loads a workbook. It has been working great for many years. We have now upgraded to Excel 2010 and have ran into some issues. After troubleshooting it seems that if i turn off the PowerPivot COM Add-In the process is able to run as it did before with no issues. While I look for the exact cause of this i wanted to see if i can turn off that Add-In just for my app. I load up Excel like this:

 Set xlApp = CreateObject("Excel.Application")
 xlApp.Visible = False

On a test Excel workbook I have this code to list the add-ins. However only "Excel Add-Ins" are the only ones that get listed. "COM Add-Ins" do not get listed.

Sub ListAddIns()
  Dim CurrAddin As Excel.AddIn
  Dim r As Long
  Dim ws As Excel.Worksheet

  Set ws = ActiveSheet
  Cells.Select
  Selection.ClearContents
  Range("A1").Select

  r = 1
  For Each CurrAddin In Excel.Application.AddIns
      ws.Cells(r, 1).Value = CurrAddin.FullName
      ws.Cells(r, 2).Value = CurrAddin.Installed
      ws.Cells(r, 3).Value = CurrAddin.Name
      ws.Cells(r, 4).Value = CurrAddin.Path
      ws.Cells(r, 5).Value = CurrAddin.progID
      ws.Cells(r, 6).Value = CurrAddin.CLSID

      r = r + 1
  Next CurrAddin

  MsgBox "Its done.", vbInformation
End Sub

After I find a way to reference the COM Add-In I need to keep it from loading in the Excel object in my app. Any help or suggestions welcome.

Thanks

Answer 1

I don't know if there is a "pretty" way to achieve this, but a "dirty" way would be to change the registry settings for the add-in before you start Excel so it won't be loaded. This can be done by setting HKCU\Software\Microsoft\Office\Excel\AddIns\\LoadBehavior to 0 (don't load automatically).
However, this is something you probably shouldn't do unless you are sure that the user accepts it, so be sure to ask the user if he agrees to this change.

You were very close with your code, the way to go is something like this:

Sub ListAddIns()
    Dim CurrAddin As **Office.COMAddIn**
    Dim r As Long
    Dim ws As Excel.Worksheet

    Set ws = ActiveSheet
    Cells.Select
    Selection.ClearContents
    Range("A1").Select

    r = 1
    For Each CurrAddin In **Excel.Application.COMAddIns**
        ws.Cells(r, 1).Value = CurrAddin.Description
        ws.Cells(r, 2).Value = CurrAddin.Application
        ws.Cells(r, 3).Value = CurrAddin.GUID
        ws.Cells(r, 4).Value = CurrAddin.Connect
        ws.Cells(r, 5).Value = CurrAddin.Creator
        ws.Cells(r, 6).Value = CurrAddin.progID
        r = r + 1
    Next CurrAddin
    MsgBox "Its done.", vbInformation
End Sub

You can use the Connect property to load and unload a COM addin.

Answer 2

I have the same problem but there's an easier solution. I Just turn the Powerpivot add-in off from the excel(untick it) and turn it on again...problem fixed.