There seems to the variation of this issue occurs. Time after time when I try to render my scene I get this message:

Octane Server doesn't crash — it keeps running, but refuses to render. To fix it I need to shut down the Octane Server and relaunch it.
I can't really say which action(s) cause it — it happens several times per hour or once in a week...
Thank you!
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A. OS Windows 7 with lastest updates at the current date
B. GTX 680 4Gb + GTX 770 4Gb
C. 24 Gb RAM
D. Nvidia GeForce Game Reay Driver 372.54
E. OctaneRender Standalone 3.02
F. OctaneRender plugin for Blender v2.25, OctaneServer v9.12
G. Blender 2.76b Octane Render edition