1.Check if Windows XP Simple File Sharing is enabled.

2.Open Windows Explorer.

3. Select the folder you want to be shared.

4.From the File menu choose the "Sharing and Security..." option.

5.Click the Network tab in the Properties window.

6. Click on Share This Folder option in the Properties window to enable sharing of this resource.

7.Click Apply or OK.
If you want you can share files by moving or copying them to the Shared Documents folder. In Windows, all files contained in the Shared Documents are automatically shared on the network.

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How to share files and folders in Windows Vista