we have developed an appliation with VS 2k5 witch has an exel addin .

It is works with Following enviroments

1- OS: xp,2k, and 2k3 with office 2k,xp,2k3 and 2k7 ( all combinations)

2- Vista with office 2k3

but it does not works with office 2k3 on vista.

What it does it will change the loadbehavior from 3 to 2.

I created a very simple addin and try it with vista + office 2k3 still does not works.

I searched for possible solution and could not find any answer yet. any help will be appreciated.

Hi,

When Add-ins in Vista perform some tasks which need administrator privilege, you can try to run Excel as Administrator (Right click Excel 2003 -> Choose Run As Administrator).

You can try to write a big try catch in OnConnection and OnStartupComplete, to see whether there’s any unhandled exception.

Did the vista have Office 2007 PIA? If so, please try to remove it.

What type of your Add-in is? If it is VSTO, I suggest you post the question on Visual Studio Tools for Office (http://forums.microsoft.com/msdn/ShowForum.aspx?ForumID=16&SiteID=1), and if it is COM Add-in, you can post on http://www.microsoft.com/communities/newsgroups/list/en-us/default.aspx?dg=microsoft.public.office.developer.com.add_ins.

I hope this helps.