Richard Siddaway's Blog

There are three pairs of file times that are available on files on Windows

PS> Get-ChildItem -Path C:\test\Newoutdata01.txt | select *time*

CreationTime : 14/04/2019 17:28:41
CreationTimeUtc : 14/04/2019 16:28:41
LastAccessTime : 14/04/2019 17:28:41
LastAccessTimeUtc : 14/04/2019 16:28:41
LastWriteTime : 25/02/2019 17:42:49
LastWriteTimeUtc : 25/02/2019 17:42:49

This is how to modify those times

Get-ChildItem -Path C:\test\*.txt |

ForEach-Object {

$date = (Get-Date).AddMonths( -(Get-Random -Maximum 5 -Minimum 1) )

Set-ItemProperty -Path $_.FullName -Name CreationTime -Value $date

Set-ItemProperty -Path $_.FullName -Name LastAccessTime $date.AddDays((Get-Random -Maximum 5 -Minimum 1))

Set-ItemProperty -Path $_.FullName -Name LastWriteTime $date.AddDays((Get-Random -Maximum 8 -Minimum 2))

}

Use Get-ChildItem to iterate through the files. For each file use Set-Property to set the value on the appropriate property. The values I’m using are purely random – you’d normally use a known value.

The *Utc version of the properties will be automatically set based on its corresponding property