this, Windows 100 1 1601 . unix, :
tUnix = tWindow/(10*1000*1000)-11644473600;
10*1000*1000, 1- 1601 , 11644473600, 1601 1970 ( unix).
, PHP:
date("d-m-Y H:i:s", $lastlogontimestamp/10000000-11644473600);
EDIT: , , . Java:
Calendar date1 = Calendar.getInstance(); date1.set(1601, 1, 1);
Calendar date2 = Calendar.getInstance(); date2.set(1970, 1, 1);
long dt = date2.getTimeInMillis() - date1.getTimeInMillis();
System.out.println(String.format("%f", dt / 1000.0));
SO: Unix/Linux Windows .