###### errors with Negative [h]:mm numbers

I have a sheet which needs to add and subtract hours, however whenever the result is in the negative I get the ######### error...how can I format the number to show negative values?

All cells are formatted as [h]:mm

Thanks!

To best describe or illustrate your problem you would be better off attaching a dummy workbook. The workbook should contain the same structure and some dummy data of the same type as the type you have in your real workbook - so, if a cell contains numbers & letters in this format abc-123 then that should be reflected in the dummy workbook.

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If you really need to see negative time under XL options select "Advanced" - Scroll down to " when calculating this wbook" - Check "use 1904 date system"

Of course when tou calculate dates you will have to take this into account