we have a application which creates some add-ins in
toolbar, when installed using setup.exe

We are trying to create .MSI file, after which the
application installs sucessfully but the addin doesn't
work it reads Error the blpmain.xla contains macro,
macro's may contain virus.

Following script is used to add Excel add-ins

Option Explicit
On Error Resume Next

' Define constants.
Const ADDIN = "C:\Program Files\blp\API\dde\BlpMain.xla"

' Load the add-ins into excel.
Dim objXL, objAddIn
Set objXL = CreateObject("Excel.Application")
objXL.Workbooks.Add
Set objAddIn = objXL.AddIns.Add(ADDIN, true)
objAddIn.Installed = true
objXL.Quit