Can I use my Mac as an external HD for my PC?

Is there a way to connect my Macbook Pro running 10.7.5 to my Dell Dimension E310 with XP to use it like an external hard drive for my Macbook?

Answer

Not exactly the way you are thinking. However the Mac does have Windows file sharing built-in to the operating system.

Open System Preferences, then select the Sharing tab. Turn on File Sharing by checking the box next to it. Over on the right you'll need to configure it to share the folders you want shared and then configure it to share using the SMB sharing protocol. Once you've enabled that, there will be a line of text that explains how to connect to your Mac from your PC.