Consider the following scenario. You run the Microsoft SQL Server 2005 Setup program to uninstall a virtual server instance of SQL Server 2005 in a cluster environment. You have more than one IP address cluster resource that is allocated to the cluster group of the SQL Server service. In this scenario, the Setup program does not remove all IP address cluster resources.
To resolve this problem, you must manually remove the remaining IP address cluster resources after you uninstall the virtual server instance of SQL Server 2005.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Steps to reproduce the behavior
Install SQL Server 2005 as a failover cluster virtual server.
Add two or more IP address cluster resources to the cluster group.
Uninstall the instance of SQL Server 2005.
Some IP address cluster resources are not removed in the SQL Server cluster group.