The area of client licenses are not automatic with XP Pro. It will drive most nuts as you will soon discover.
http://www.microsoft.com/windowsserver2003/howtobuy/licensing/caloverview.mspx
In a nutshell, CALs were not automatically granted with a copy of XP Pro. You may find it hard to find the old Windows 2000 link/webpage about this but it gave everyone pain as they discovered the awful truth.
Bob
I am rebuilding a Windows 2000 server, and have come to find out that my organization does not have their OEM install disc. I am pricing the OS and the price depends on the number of clients, as you know. All of their clients have OEM Windows XP Pro licenses. So, does it matter, for example, if I buy a 5-client version of the Server OS or any number, if all my actual clients are independently licensed? Will I notice any differences in the operating system at all?
Frank

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