We have a build that we are testing against Vista and against Outlook 2007.  This build uses the latest version of VSTO 2005 that is compatible with both Office 2003 and Office 2007.

http://download.splendidcrm.com/SplendidCRM_Plug-in_for_Outlook_1.4.2634.36765_Beta.exe

Have your customer give this build a try, but make sure to provide feedback. 

One thing we noticed on Vista is that Outlook had to be run at least once as Administrator (right click on Outlook icon and select "run as Administrator") after installing the plug-in.  We have asked MS for help on this, but we have not heard back.

Well, I had some trouble initially.  After many failed attempts to merely open Outlook 2007, I noticed that the PIA were not installed.  The install you gave me gave the illusion that it was installing the PIA, but it was never laid down.  After closer inspection, the install attempted to load PIA 2003 (which went very quickly so I am guessing nothing was done).  No PIA entry could be found within Control Panel Add/Remove. 

I downloaded the 2007 PIA at http://www.microsoft.com/downloads/details.aspx?familyid=59daebaa-bed4-4282-a28c-b864d8bfa513&displaylang=en

Then I reinstalled the Plugin (BTW, all dialog screens that refer to the application being installed refer to Splendid Plugin for Outlook 2003 instead of 2007). 

I was then able to open Outlook and saw the Splendid Plugin Toolbar and Menu Items.  But I had to stop testing here because of changes I had made to the 2003 Plugin. 

I have the Source code for the 2003 Plugin.  Before we went live, I noticed some strange behavior with the password storage for the Plugin.  It is difficult for me to remember what the issue was.  I may have made the change because the user's password was not encrypted within the application setup files (within user's local settings for splendidcrm).  I do recall strange behavior where I would 'Test Connection' and the connection would work.  Then I saved the settings, opened up the settings, attempt to test the connection again and got an error.  The plugin was not properly handling the state of the password (the password box was prefilled with the encrypted version of the password or something like that).  Anyway, I used my own MD5 encryption utility and encrypted the password for storage within the setup file.  I then fixed the logic within the plugin so a user could select the 'Test Connection' button at any time.  The short end of it, my soap file is using a different encryption methodology than the new 2007 plugin so logins are failing. 

I would like to continue testing the 2007 plugin, but I need to get around this login issue.  Any ideas on how we can move forward?