I'm using Excel 2000 and have a workbook with several worksheets. I have a worksheet that summarizes data from the others and to do so I have many cells in it that are simply links to other cells on other sheets. This evening I added a few more sheets with various data items and now many of the "linked" cells simply do not update when I make changes to the cell it's linked too. Very strange. It's as if there is an "update cell" function that simply isn't happening. The auto calculate option is turned on and I've done manual calculations as well - no good.

Any ideas?

Thanks, Don

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