From: satyanarayana K on
Actually what happen is Asp.Net by Default support MM/DD/YYYY...
so if u provide the date in dd/mm/yyyy format it will show the error(some
cases means MM>12).
so,u only write one method to convert to from MM/DD/yyyy to DD/MM/yyyy.

ex:
//read the value into one variable
Datetime dtm=textbox.text

//convert the Datetime to DD/MM/YYYY
//using DateFormat_MMddyyyy method (user method )

DateTime Dt = Convert.ToDateTime(DateFormat_MMddyyyy(dtm.ToString()));

//Now define the method

pulic static string DateFormat_MMddyyyy(string dtm)
{
DateTime dt = DateTime.ParseExact(dtm,"MM/dd/yyyy", DateTimeFormatInfo.
InvariantInfo);
return dt.ToString("dd/MM/yyyy");
}

url:http://www.ureader.com/msg/14485962.aspx