I'm running the following code in an Excel macro, to open up a powerpoint
document from within Excel. It works fine on my computer and on the
computers of two other users. When I try to run it on one computer, though,
I get an error message "Library Not Registered" when it gets to the line "Set
app = New PowerPoint.Application". Any thoughts of how to fix this would be
greatly appreciated...THANKS!

Function GetPPT() As PowerPoint.Presentation
'this procedure opens a powerpoint presentation for output
Dim app As PowerPoint.Application
Dim strFile As String


strFile = Application.GetOpenFilename("(*.ppt), *.ppt", , "Open File")

If strFile = "False" Then

Else
Set app = New PowerPoint.Application
app.Visible = msoTrue
Set GetPPT = app.Presentations.Open(Filename:=strFile, ReadOnly:=msoFalse)
End If

End Function