I upgrade from NIS 2011 to NIS 2013 four days ago on 25-Jan-2012 (clean install after uninstall of NIS 2011 and two wipes with NRT) and noticed that Quick Scan is not running automatically during system idle. The Norton Insight task runs during idle as expected, and LiveUpdate has downloaded and installed the Norton 2013 Virus Definitions several times since the upgrade.
My system clock is correct and my laptop is always plugged in. Reducing both the Idle Time Out and Automatic Tasks Delay to 1 minute (Settings | General | Norton Tasks) and leaving my system idle until it goes into sleep mode (25 min) has no effect. Quick Scan will run to completion if I force it to run manually from the Norton Tasks window.
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Windows Vista Home Premium 32-bit SP2 * NIS 2013 v. 20.2.0.19 * IE 9.0 * Firefox 17.0
HP Pavilion dv6835ca, Intel Core2Duo CPU T5550 @ 1.83 GHz, 3.0 GB RAM, NVIDIA GeForce 8400M GS