Alright. Enough background; let's get down to business.
On a clean installation of XP, file sharing is disabled. Even though the Server service is running, you can't share out a folder. XP makes you step through the Network Setup Wizard (NSW) first. You can run through the wizard at just about any time, and you will be prompted to do so if you try to share out a folder before the NSW has run.
And, even if you've run it before, you can still run it again at any time to reflect any network configuration changes. (If you understand what's being presented in the networking chapters of this book, however, I don't think you'll ever need to.)
Nevertheless, it's a necessary evil if our goal is sharing. To run the Network Setup Wizard and allow sharing, follow these steps:
The Network Setup Wizard also tries to configure a firewall-protected Internet connection, among other things, but the only thing we're focusing on here is the "File and printer sharing" dialog box. The firewall details are discussed later.
When you enable file and printer sharing, the Guest account is enabled. All activity on an XP machine occurs in the context of a user account, and the Guest account is a built-in account specifically intended for users who don't have regular accounts on the computer. No password is assigned to the Guest account, although this account will not display on the Welcome screen. If you want it displayed at startup time, open the "User Accounts" applet in the Control Panel, select the Guest account, and turn it on.
From now on, all network access to shared folders is made through one account and one account onlythe Guest account. Oh, and something else: this applies only if using XP's default Simple File Sharing (SFS), rather than classic sharing. That's righttwo flavors of sharing are available in Windows XP. The differences between the two are fleshed out in the sidebar and in the next couple of chunks.