Wrong date in Excel 2007 built-in calendar!!!

[machiuyeungsunny]

Excel system assign the date 1900/1/1 as day 1. 1900/1/2 as day 2, etc.

I found that the Excel built-in calendar consists of a serious mistake. As
year 1900 is NOT a leap year, it should NOT have the day 1900/2/29. However,
I can actually find that day in the Excel built-in calendar naming it as day
60. The result is all days after 1900/2/29 are one day later than the actual
day. It actually causes great problem when I have to create own VB calendar
functions as all the days are wrong.

Will microsoft correct this problem?

 

[Sheeloo]

This is by design -
"When the date system in Microsoft Excel was originally created, it was
designed to be fully compatible with date systems used by other spreadsheet
programs.

However, in this date system, the year 1900 is incorrectly interpreted as a
leap year. Because there is no February 29 ("leap day") in the year 1900, the
day of the week for any date before March 1, 1900 (the day after the "leap
day"), is not computed correctly.

Note that this only affects dates before March 1, 1900, and that the error
only occurs when you use the 1900 Date System in Microsoft Excel.

This problem does not occur if you are using the 1904 date system. When you
use the 1904 date system and the WEEKDAY function to compute the day of the
week for dates prior to January 1, 1904, the function returns a #VALUE!
error. "

So actually the dates before 2/29/1900 are wrong... dates after that are OK.