1)
you could call the following sub from the workbook's open event:

Sub testAddIn()

Dim ai As AddIn

For Each ai In Application.AddIns
If ai.Name = "ATPVBAEN.XLA" Then
ai.Installed = True
Exit For
End If
Next

End Sub

this add-in is a standard part of the excel installation, so you shoul;d not
need to port it with the workbook.

2 & 3) use DateDiff
note the 2nd 'f' in xl2007 :)


"cate" wrote in message
...
I have discovered that contrary to the IT dept, all company users do
not have identical installations. Well, that's not really that
surprising. Anyhow, I have distributed a wb that has an additional
add-in (analysis tool kit). I have also installed a reference to it
in VBA.

How does someone check to see what is installed? Then what do you do
about it? Can you install it with a VBA program? Is there a way to
'bring along' your add-ins with the wb?


#2
And I've also discovered, here in this group, that DATEDIF was damaged
in an Excel2007 spak. How would I check to verify the release level
and spaks installed?

#3
Is there a replacement for DATEDIF?