Sometimes, You may to retrieve the User details such as User’s Email, Account ID, Full name, etc from the Created by field. Here is the PowerShell script to get created by field values in SharePoint.

PowerShell to Get “Created By” Field Value in SharePoint:

Add-PSSnapin Microsoft.SharePoint.Powershell -ErrorAction SilentlyContinue
#Configuration Parameters
$WebURL = ""
$ListName = "Questionnaire"
$ItemID = "147"
#Get the Web, List, Item objects
$Web= Get-SPWeb $WebURL
$List= $web.Lists[$ListName]
$Item = $List.GetItembyID($ItemID)
#Get the "created by" Field value
$Author = New-Object Microsoft.SharePoint.SPFieldUserValue($web, $Item["Author"])

#Get Email ID from Created By
#Get Login ID
#Get Created By Full Name

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