The amount of time the “New” icon is shown in SharePoint 2010 can be changed at the Web Application level using PowerShell.
Below are examples to get or change settings for the icon:
Get the current Duration of New-Icon
$webApp = Get-SPWebApplication "http://webAppURL/"
$webApp.DaysToShowNewIndicator
$webApp.DaysToShowNewIndicator
Change the duration of Displaying New-Icon
# Set to 1 Day
$webApp = Get-SPWebApplication "http://webAppURL/"
$webApp.DaysToShowNewIndicator = 1
$webApp.Update()
$webApp = Get-SPWebApplication "http://webAppURL/"
$webApp.DaysToShowNewIndicator = 1
$webApp.Update()
Prevent the New-Icon from Display
Prevent the New-Icon from Display
# Essentially, just set the display duration to 0 days.
$webApp = Get-SPWebApplication "http://webAppURL/"
$webApp.DaysToShowNewIndicator = 0
$webApp.Update()