If you find yourself in this situation where you are still working with SQL Server 2000 and are wanting to upgrade to SQL Server 2005 then you are going to want to run the Upgrade Advisor to check what work that you need to do prior to the upgrade being undertaken.
You can download SQL Server 2005 Upgrade advisor here. Once you have installed the upgrade advisor, if you happen to receive an error – “Analyze SQL Server” with a Status of error. You are potentially not going to receive any further information.
To get around this issue if you open up Windows Explorer and navigate to C:Program FilesMicrosoft SQL Server 2005 Upgrade AdvisorBPA. Under this folder to resolve the issue create a new sub-folder – “BPAClient”. Inside of BPAbin you you will see there is a file named BPAClient.dll. Copy this dll file into your newly created BPAClient sub-folder and re-run upgrade advisor.