Does this mean that existing links no longer update?

Or that you can't create a new link by Copy|paste special|paste link?

If it's the first, if you select the cell with the formula, and hit F2, then
enter, does the cell re-evaluate?

If it's the second, make sure both workbooks are open in the same instance of
excel.

Scott D wrote:

All of a sudden I can't get a cell to link to another workbook in excel
2007. This has never happened before. It is as if the workbooks are not
seeing each other. not working with existing or new workbooks.

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Dave Peterson