title: C# Unix Timestamp to DateTime
body: <p>I appreciate that this question has been covered many times over in various forms, but none seem to help with the particular problem that I'm experiencing. I have the following method that I use to convert incoming data to a C# <code>DateTime</code> variable. The trouble is, the company sending the data in are claiming that I'm converting it incorrectly because the times are appearing one hour behind in my system. I would assume that this is something to do with British Summertime, but is the problem at my end, or at their end, because I thought the method below would be taking account of British Summertime by the fact I'm using <code>ToLocalTime</code>? Any help would be gratefully accepted.</p>
  
  <pre><code>private DateTime ConvertTimeStamp(double t)
  {
      return new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc)
          .AddMilliseconds(t)
          .ToLocalTime();
  }
  </code></pre>