Navision Business Notification install fail !

HI all,

I have a problem when installing Navion business notification server, i get the following Error message : “Unregistration of SQL notification services failed” and the installation is canceled

I’m using a test environment includig :

Windows 2003 standard R2 , with all update and Main Domain controller

SQL server 2005 SP2

Navision 2009 SP1

All authentifications are windows based.

Thnaks for your help.