In the night all my cgminers on win32 died all at the same time.
I believed you the first time. What I don't have, as yet, is an explanation or anything in particular to debug since I can't reproduce it yet.
Maybe if you run one instance in debug mode (-D -T) you can see what the last thing is that is logged.
For finding the error i am running one instance with -fix-protocol.
I had the idea maybe the Exception comes when the DSL-Router makes a reconnect and stratum looses his tcp connection.
Logging is also enabled now.