The value is a Unix Time, defined as seconds since 1970-01-01T00:00:00,0Z. Important is the Letter Z, you live in Sweden, in consequence you must add 1 hour for StandardDate and 2 hours for DaylightDate to the date. The infos you can get with GetTimeZoneInformation. But you must determine, which Bias (Standard or Daylight) is valid for the date (in this case -60). You can convert the date value with the function below.

 

The Date for 977347109 is 2000-12-20T22:18:29+01:00.

 

Code:

const UnixDateDelta = 25569; { 1970-01-01T00:00:00,0 } SecPerMin = 60; SecPerHour = SecPerMin * 60; SecPerDay = SecPerHour * 24; MinDayFraction = 1 / (24 * 60);   {Convert Unix time to TDatetime}   function UnixTimeToDateTime(AUnixTime: DWord; ABias: Integer): TDateTime; begin Result := UnixDateDelta + (AUnixTime div SecPerDay) { Days } + ((AUnixTime mod SecPerDay) / SecPerDay) { Seconds } - ABias * MinDayFraction { Bias to UTC in minutes }; end;   {Convert Unix time to String with locale settings}   function UnixTimeToStr(AUnixTime: DWord; ABias: Integer): string; begin Result := FormatDateTime('ddddd  hh:nn:ss', UnixTimeToDateTime(AUnixTime, ABias)); end;   {Convert TDateTime to Unix time}   function DateTimeToUnixTime(ADateTime: TDateTime; ABias: Integer): DWord; begin Result := Trunc((ADateTime - UnixDateDelta) * SecPerDay) + ABias * SecPerMin; end;   procedure TForm1.Button4Click(Sender: TObject); begin Label1.Caption := UnixTimeToStr(977347109, -60); end;