Update Created By (Author) column of SharePoint document using PowerShell

Modify the Created By (Author) site column using PowerShell script

The below script will update the "Created By" site column (also known as document Author) of a SharePoint document or list item.

⚡️ Note - This requires updating the Author and Editor attributes both.

$spWeb = Get-SPWeb -Identity "http://sharepoint_site_url"
$spList = $spWeb.Lists["Shared Documents"]
$spItem = $spList.GetItemById(1)

$SPFieldUserValue = New-Object Microsoft.SharePoint.SPFieldUserValue($SPWeb,1, "LastName, FirstName")

$spItem["Author"] = $SPFieldUserValue
$spItem["Editor"] = $SPFieldUserValue

Make sure you specify the username correctly.