I've done it often myself.
Initially I will have both workbooks open as it is just easier to highlight a cell in my target workbook, press the = sign, then highlight the cell in the source workbook, and press Enter. This provides the link in the correct format.
Then, I save the source workbook and close it down. That way the link in the target workbook changes to the full path. Then any future changes I make to the source workbook are picked up in the target book, even if the source workbook is closed at the time I have opened the target workbook.
What happens when you try this?
Mark
I am using Excel '03 on a WinXP system. I created a spreadsheet with references to cells in another workbook. It seems I have to open the source workbook to get my new sheet to update the data. I thought since I already had the full path ref in my cells, that Excel would be able to just go out to the other file and grab the data without me having to open the other (source) workbook.

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