Well, it's been a very long time ago when I did this but I will try. This is for OS XP SP2. Not sure about Vista.

Is the new HDD an external plug n play?? Hope so. anyway I'm sure you have it ready to go. When you plugged it in, your computer recognized it as a Letter: i.e. D: drive.
You can try this with one file to see if it works.

In Limewire go to Tools > Options > Saving. Here I created a new save folder, L:\ shared
Make sure to click apply & OK.
Now go to the existing shared folder on C: Drive. Left click any file... See file and folder task left of the files.
Click move file and a pop up window will appear. Now direct the file to the new Drive. If it works now you can right click on the whole folder at the top of the page and direct it to the new drive, and it will start transfering the files to the new save folder.

If anyone else has anything to add please feel free as I said above it has been almost a year since I did mine.

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