Using Excel 2004 on a Mac. A workbook with 20+ worksheets with lots of interconnected formulae using named cells. The names (of the cells) appear to have started duplicating themselves. This started after a major edit with several insertions and deletions of worksheets (which has been done many times before without this problem). The multiple names will not delete and there are now up to 12 identical names for exactly the same cell. Also some of the cells that use these names are not updating, but rather presenting #NAME? - this can be resolved by finding the name through: Insert,Name,Define and clicking it - however this sometimes results in it creating yet another name.