Hi i also had the same problem my applications will be running in localhost but when i use IIS or apache it will throw the error String was not recognized as a valid DateTime.After a lot of search i finally got the solution
just declare ur date field as
System.DateTime str_date=DateTime.Parse(sel3.Text,System.Globalization.CultureInfo.CreateSpecificCulture("en-AU").DateTimeFormat);
I hope it will work fine in ur application
Thanks in Advance,
N.ThillaiArasu,
http://nthillaiarasu.blogspot.com
N.ThillaiArasu