TIP - Permissions required to run SQL Server setup?

When you try to install SQL Server 2005, the setup wizard runs under setup.exe. This service then adds registry keys, creates folders, grant privileges to the startup account etc.

All this can only be done is the setup is run under an administrator account.

Setup on Standalone Servers

If you are installing SQL 2005 on a standalone server, then log on with an account that is part of the local administrators group on the machine and then launch the setup wizard to install SQL 2005.

If your SQL Server setup files are lying on a remote share, then your account should also have administrative privileges on the remote share.

Setup on Clustered Servers

From BOL - To create a failover cluster, you must be a local administrator with permissions to logon as a service, and to act as part of the operating system on all nodes of the virtual server.

Note that although you need administrative privileges to install SQL 2005, you don’t have to run SQL Server under an admin account.