Microsoft Office

Part IV
Using Advanced Excel Features
Avoiding Potential Problems with External
Reference Formulas
Using external reference formulas can be quite useful, but the links may be unintentionally severed. As long
as the source file hasn’t been deleted, you can almost always re-establish lost links. If you open the workbook
and Excel can’t locate the file, you see a dialog box that enables you to specify the workbook and recreate
the links. You also can change the source file by using the Change Source button in the Edit Links
dialog box. The following sections discuss some pointers that you must remember when you use external
reference formulas.
Renaming or moving a source workbook
If you rename the source document or move it to a different folder, Excel won’t be able to update the links.
You need to use the Edit Links dialog box and specify the new source document.
NOTE
If the source and destination folder reside in the same folder, you can move both of the files
to a different folder. In such a case, the links remain intact.
Using the Save As command
If both the source workbook and the destination workbook are open, Excel doesn’t display the full path
in the external reference formulas. If you use the Office ➪ Save As command to give the source workbook
a new name, Excel modifies the external references to use the new workbook name. In some cases, this
change may be what you want. But in other cases, it may not. Bottom line? Be careful when you choose
Office ➪ Save As with a workbook that is the source of a link in another open workbook.
Modifying a source workbook
If you open a workbook that is a source workbook for another workbook, be extremely careful if the
destination workbook isn’t opened. For example, if you add a new row to the source workbook, the cells
all move down one row. When you open the destination workbook, it continues to use the old cell
references — which is probably not what you want.
You can avoid this problem in the following ways:
n
Always open the destination workbook(s) when you modify the source workbook. If you do
so, Excel adjusts the external references in the destination workbook when you make changes to
the source workbook.
n Use names rather than cell references in your link formula. This approach is the safest.
The following link formula refers to cell C21 on Sheet1 in the budget.xlsx workbook:
=[budget.xlsx]Sheet1!$C$21
If cell C21 is named Total, you can write the formula using that name:
=budget.xlsx!total
Using a name ensures that the link retrieves the correct value, even if you add or delete rows or columns
from the source workbook.
CROSS-REF
See Chapter 5 for more information about creating names for cells and ranges.
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