Hi kem104, I want to help you to solve your problem.
As I understand, you get a 403 error when you want to rename a SharePoint URL of a list item via Powershell, right?
Firstly, why do you use the SDK and not the widely used PNP module of PowerShell?
Is it possible to try it with the following example code:
SharePoint online site URL
$siteUrl = "https://contoso.sharepoint.com/sites/SPConnect"
Current display name of SharePoint
list $oldListName = "Images List"
New list URL $newListUrl = "Lists/LogoUniverse"
#New display name for SharePoint list
$newListName = "Logo Universe"
Connect to SharePoint online site
Connect-PnPOnline -Url $siteUrl -Interactive
Get the SharePoint list
$list = Get-PnPList -Identity $oldListName
Move SharePoint list to the new URL
$list.Rootfolder.MoveTo($newListUrl)
Invoke-PnPQuery
Rename List Set-PnPList -Identity
$oldListName -Title $newListName
If you get the same error, we can check and troubleshoot again what's going on there and what could cause the problem.
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