Hi All, Had a few instances on several different 64-bit Win7 SP1 machines where "ESET NOD32 Antivirus Business Edition (64-bit) v4.2.76" freezes/hangs the machine. The CPU usage even when using systernals process monitor does not show esets kernal service as been the culprit but after doing all the investigation what can cause the hangs on these machines, I find that by un-intsalling v4.2.76 the problem goes away. Our config files remained un-changed and are uploaded to each client after upgrades but this has no effect, the machines still hang. Event logs show no obvious warnings and no BSOD's reported for any kernal dumps to use. Your advice on this as we want to progress in the upgrades of all our 64-bit machines and eventually the BE edition of v5.