http://blogs.msdn.com/b/bclteam/archive/2010/11/28/time-travel-with-net-or-datetime-datetimeoffset-and-the-lost-dst-hour-greg.aspxEvery year again comes the DST change... And every year again do we need to work with customers on helping them understand some legacy design decisions, and how to work around these ghosts of the past. Recently, around the end of October and the starten-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)http://blogs.msdn.com/b/bclteam/archive/2010/11/28/time-travel-with-net-or-datetime-datetimeoffset-and-the-lost-dst-hour-greg.aspx#10116618Mon, 17 Jan 2011 15:57:14 GMT91d46819-8472-40ad-a661-2c78acb4018c:10116618BCL Team<p>Hi osexpert,</p> <p>The answers to your questions are in the further reading links above. In particular, these will be the most relevant ones:</p> <p><a rel="nofollow" target="_new" href="http://msdn.microsoft.com/en-us/library/bb384267.aspx">msdn.microsoft.com/.../bb384267.aspx</a></p> <p><a rel="nofollow" target="_new" href="http://blogs.msdn.com/b/bclteam/archive/2007/06/18/a-brief-history-of-datetime-anthony-moore.aspx">blogs.msdn.com/.../a-brief-history-of-datetime-anthony-moore.aspx</a></p> <p><a rel="nofollow" target="_new" href="http://blogs.msdn.com/b/bclteam/archive/2007/07/12/a-brief-history-of-datetime-follow-up-anthony-moore.aspx">blogs.msdn.com/.../a-brief-history-of-datetime-follow-up-anthony-moore.aspx</a></p> <p>One of the advantages offered by DateTimeOffset is that it allows to represent a point in time unambiguously, and yet allows to specify a local time without referencing a particular geo-political time zone. This allows for instance persisting local times without persisting all relevant time zone and DST rules (as they may change over time). Please refer to the above links for further details. </p> <p>Thanks,</p> <p>-Greg</p> <div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=10116618" width="1" height="1">http://blogs.msdn.com/b/bclteam/archive/2010/11/28/time-travel-with-net-or-datetime-datetimeoffset-and-the-lost-dst-hour-greg.aspx#10103574Sat, 11 Dec 2010 12:39:19 GMT91d46819-8472-40ad-a661-2c78acb4018c:10103574osexpert<p>I don&#39;t understand why DateTime/DateTimeOffset was not designed to simply hold the UTC time, and nothing more. The local time can easily be calculated when you need it. This is like Windows always did it: time stamps in NTFS is UTC, and there never was any problems until .NET came along?</p> <div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=10103574" width="1" height="1">http://blogs.msdn.com/b/bclteam/archive/2010/11/28/time-travel-with-net-or-datetime-datetimeoffset-and-the-lost-dst-hour-greg.aspx#10097644Mon, 29 Nov 2010 09:23:32 GMT91d46819-8472-40ad-a661-2c78acb4018c:10097644Isiah<p>Thanks for the post, Now I know what is wrong with my HTC HD2 running on windows mobile 6.5 </p> <div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=10097644" width="1" height="1">