ammi84: If there's nothing in CGWatcher's log then it's difficult to say why the miner closed unexpectedly. It's not something I've run into. I would suggest enabling the monitoring option "Ensure miner stays running unless stopped by CGWatcher" and see if this helps prevent downtime.
thank you

could the windows event log help you perhaps?
i found some errors in the logfiles of windows
Name der fehlerhaften Anwendung: CGWatcher.exe, Version: 1.3.5.0, Zeitstempel: 0x52d717bb
Name des fehlerhaften Moduls: clr.dll, Version: 4.0.30319.18444, Zeitstempel: 0x52717f9a
Ausnahmecode: 0xc0000005
Fehleroffset: 0x000000000017f0ba
ID des fehlerhaften Prozesses: 0xa80
Startzeit der fehlerhaften Anwendung: 0x01cf2dfa2b590009
Pfad der fehlerhaften Anwendung: C:\Users\basti\Desktop\CGWatcher-1.3.2\CGWatcher.exe
Pfad des fehlerhaften Moduls: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Berichtskennung: a5c5ac1f-9a35-11e3-ad95-f3539813e294
Application: CGWatcher.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an internal error in the .NET Runtime at IP 000007FEF8FDF0BA (000007FEF8E60000) with exit code 80131506.
... my next step: repair .net 4.5 installation
i will report