Thanks jcl. Sorry about "crash" - I do know better... frown How's this:

Code:
Faulting application name: Zorro.exe, version: 1.9.6.4, time stamp: 0x5bec3864
Faulting module name: Zorro.exe, version: 1.9.6.4, time stamp: 0x5bec3864
Exception code: 0xc0000005
Fault offset: 0x0018acfe



The above was copied from Event Viewer. Windows popped up the crash window containing this just after the startup lookback message posted in Zorro's window.

FWIW, my experience with using -diag with the Z Systems hasn't shown either huge files nor serious slowdown... But I'll not ignore your recommendation. laugh Especially with strategies that handle more Assets and/or trade more frequently...

Thanks.