retrieving date& time from elapsed time string

[ccodenewbie]

Hi All,

This is a bit tricky to explain so please bear with me.

I am trying to get Window's "System" process starttime. The closest I have come to doing so is by using

 long st = procs.StartTime.ToFileTime();
DateTime Dt = new DateTime(1601, 1, 1,0,0,0).AddSeconds(st);
string stime = String.Empty;
stime += (Environment.TickCount / 86400000).ToString() + ",";
stime += (Environment.TickCount / 3600000 % 24) + ",";
stime += (Environment.TickCount / 120000 % 60) + ",";
stime += (Environment.TickCount / 1000 % 60);

which gives me (for e.g) 7,10,22,48

How can I convert the stime string into a datetime so that I can subtract it from DateTime.Now to get the process's starttime in the format dd/MM/yyyy HH:mm:ss?

This doesn't work btw

DateTime result = DateTime.Now - new TimeSpan (stime);