Excel/Excel 2010


I have created an excel workbook  that has about 12 worksheets.  In all worksheets I have a column for the date.  The date format is set to this:  12-Jan-15.  This is my problem:  About once every two weeks when I open the spreadsheet the date column is filled with plus signs (######).   Somehow, excel automatically changes the date format.  When I check the “format cell” option, it shows the format as:  “Monday, January 12, 2015”. When I change the format back to “12-Jan-15”, the pound signs go away and the proper format reappears.  Could you tell me why excel changes format on its on?

the # signs indicate that the cell isnt big enough to display the data, but I've never come across excel reformatting on its own - if it was a custom format and the settings for that format were changed, this would be a possibility, but my GUESS would be that the cell is not quite wide enough to display all dates in the format you want, so I'd try widening it a little and see if the problem disappears.
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Aidan Heritage


I have provided first hand support since `95 for Microsoft Office majoring in Word and Excel - support for all versions from 2 onwards. I'm based in the UK, so please allow for time differences when asking me questions from other parts of the world!


My background is in the insurance industry and call centre areas, but have been called upon to provide many varied solutions.

I'm educated to UK A level standard, but as I left school some 30 years ago that is rather irrelevent - university of life has provided more of a background!

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