Failed To Open Discovery On Machine: 'xxxxx'

SQL Server 2005 setup fails with the following errors in the setup log:

Failed to find property "ComputerList" {"SqlComputers", "", ""} in cache
Failed to open discovery on machine: 'xxxxxx'

Resolution:
Check network properties to see if "File and Printer sharing" is enabled. If not, enable it and attempt the installation again.

Installation Package for the Product Microsoft SQL Server Native Client cannot be found

SQL Server 2005 installation fails with the following error:

An installation package for the product Microsoft SQL Server Native Client cannot be found. Try the installation again using a valid copy of the installation package 'sqlncli.msi'

 Resolution:
Search for the file 'sqlncli.msi' in the installation CD / folder, double click it and select uninstall. Restart the installation.

Error 5184: Cannot use file 'xxxxx' for clustered server

This error occurs when the disk that you're trying to restore/attach the database file to does not have a dependency on the SQL Server resource in the cluster. It isn't enough to have the resource in the same cluster group.

Resolution:
Take the cluster group offline, add the disk dependency to the SQL Server resource, then bring the cluster group back online.