Couldn't say exactly, but once or twice a week. I know one thing for sure, it wasn't consistant like a timer varible rapping, hence the need to run a nightly script just to catch it, if it was hung.
The only thing I'm doing out of the norm is running 5 instances from a shared directory, each with their own config. They run as a (SYSTEM) service (connected to the console session.) A couple run the RACE MANAGER insim app also.
Anyhow I'll keep you posted on the results. Should it go a miss again, I'll leave it in the state for you to investigate. If necessary I can arrange access to the box if it helps.
Rob