That's what Excel does; it cannot work with negative time/dates
You could try =ABS(A2-A1) and have a flag in an adjacent cell
=IF(A2<A1,"Neg","Pos")
best wishes
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Bernard V Liengme
www.stfx.ca/people/bliengme
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"Amr Shehata" wrote in message
...
I have two cells that carry two different times as follow
cell A1 has 00:05:00
cell A2 has 00:04:00
cell A3 should display the difference in negative way(-00:01:00). I only
get
##### instead of the answer in cell A3 and a message reads (negative dates
or
times are displayed as # # # #) Your help will be much appricated. thanks