In previous releases of Windows Server, the updates were installed during a maintenance period and rebooted if required right after the update. The day and time was configurable so that this would have minimal effect during peak hours.
This however changed in Windows Server 2012. The default setting downloads the available updates and notifies the user and requires user action within one day. After one day the updates are installed as soon as possible and forces reboot on the server. On production servers this is not appropriate behaviour as it may force reboot at critical time causing very unpredictable downtimes.
Luckly this can be configured although it’s not located in same place as in previous versions of Windows Server. Here’s a step by step tutorial on how to configure the updates to automatically install at 3am on Sundays:
1. Open the Local Group Policy Editor
Either search for “Edit Group Policy” or open the gpedit MMC snap-in using Run