If you just need to reformat a correct date to show up as dd/mm/yyyy, just use the "Format Cells" command and set a custom format string to exactly that. If, on the other hand, you are finding that Excel just doesn't get that the first value is a DAY, not a month, such as trying to graph a temperature data logger that records data in dd/mm/yyyy:
Reformat the strings as dd/mm/yyyy, using the first method. This will make them LOOK correct, even though the actual date VALUES are still day-month inverted. Now save the table as a .CSV file. This will save the dates as plain text in the correct order, which you can then re-import and have Excel now read the correct date value. 🙂
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Ryan R.
R&D