Well, addins don't get disabled for no reason. If the addin is in its own
AppDomain, and all VATO addins are in their own AppDomain, then only a
couple of things will cause an addin to become disabled.

If the user installs the addin while Outlook is running that will cause the
problem. Any unhandled exceptions in the addin will also cause the addin to
become disabled.

So if the addin starts out disabled the reason is going to be one of those
two things.

AFAIK there is no difference that should be there for the addin no matter
what version of Windows XP the user is running.

--
Ken Slovak
[MVP - Outlook]
http://www.slovaktech.com
Author: Professional Programming Outlook 2007.
Reminder Manager, Extended Reminders, Attachment Options.
http://www.slovaktech.com/products.htm


"Nagaraj" wrote in message
...
Thanks Ken for the information.

You are right. It is a VSTO project. Assemblies are strongly named. I am
deployting VSTO second edition runtime and Preop assemblies 2003 along
with
.NET framework 2.0. The addin is loaded correctly at the location

Tools-Options-Other-Advanced Options-COM-Addins

with Load Behaviour : Load at Startup

But the add-in is not checked.

The add-in is there in Disabled Items. If we enable it then it is working
in
the client machine. But my client wants to enable it immediately after it
loads.

Since he is having XP home SP2 instead of XP professional is there any
security updates required at his system?
--
Nagaraj Tadipatri