The registry entries for the addin have to be written to either HKCU or
HKLM. For HKCU you would have to write out those values for every different
Windows logon. Are your entries for the addin (LoadBehavior and so on) being
written out to the user computer/logon? If not that's the problem.

We have exactly the same problem.

We have developed a VSTO 2005 add-in for Outlook 2003 which works perfects on our machines, but will not work on the Terminal Server (Windows 2003 Server) used by our client.

The strange thing is that we don't get a Com-error or something like that, but the Add-On just will not appear in the list with COM Add-Ons in their Outlook 2003 Client. Exactly like the original client.

We do the following to add our Add-In to Outlook.
1) Installed the Office 2003 Primary Interop Assemblies redistributable package.

2) Installed the VSTO 2005

3) Installed our plugin. This uses the installer created by VSTO for Visual Studio 2005.

4) Added the Runtime Security policies to .NET 2.0 for our signed DLL's. We give Full Rights to our signed DLL's on the Enterprise, Machine and User 'All Code Groups'.

5) For each user we add the registry keys in HKEY_CURRENT_USER\Software\Microsoft\Office\Outlook\Addins\OURPLUGIN

All software is installed using "control Panel/Add Remove programs" with admin rights because it's a terminal server.

We have also installed the Add-In on another machine within their organization (Also Running Windows 2003 Server) and there it's working without any problems. But that Server is not configured as a Terminal Server.

Is the solution for this problem already found, and could you please share the solution for this?

Regards,

John Belmer
Avance Information Management