I had this problem all the time at work. I can't test for it now because this rig doesn't have Office installed.
I bet, if that summary.xls workbook is open at the time you look at this link, the link just shows as summary.xls. But as soon as you close that summary.xls, the full link re-appears.
That's all by design, because if summary.xls is not active then Excel needs the full path to find this reference.
I'm not sure I understand the system you have with new folders, but try this;
With both workbooks open, and with focus on the workbook you want to place the link in, highlight the cell you want the link to be in and type the = sign. Now, move to the summary.xls workbook and highlight the cell that you are linking to and press Enter. This should place the external link in the workbook you are working on.
Now, return to the summary workbook and Save as, to the new location you want. This will at least create the link to the correct summary.xls workbook. But as soon as you close summary.xls, the full path will appear in the target workbook.
This is what Microsoft says about this;
Formulas with links to other workbooks are displayed in two ways, depending on whether the source workbook ? the one workbook that supplies data to a formula ? is open or closed.
When the source is open, the link includes the workbook name in square brackets, followed by the worksheet name, an exclamation point (!), and the cells that the formula depends on. For example, the following formula adds the cells C10:C25 from the workbook named Budget.xls.
Link =SUM([Budget.xls]Annual!C10:C25)
When the source is not open, the link includes the entire path.
Link =SUM('C:\Reports\[Budget.xls]Annual'!C10:C25)
So it seems that you cannot do what you wish precisely, but of course you can always cheat. For example, hide that cell, (either hide the column or row), then use another cell to copy the contents that cell finds.
Sorry, but I hope that helps.
Mark
I am using a workbook reference in a cell that contains [summary.xls]. I want it to always refer to the summary.xls workbook that I have open at the time. However, Excel always converts it to a full file path (ie. C:/070410/summary.xls). I want it to just refer to the one I have open, as we create new folders per week, using the same filenames. It always wants to go back to the last one I used. Is there a way I can get it to just refer to the open one, and not have to change the references in all the cells each time? Any help greatly appreciated! My OS is Win XP.

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