PowerShell Script to Reset Permissions on all Documents in a Document Library in SharePoint Online.

Here's a PowerShell script that resets permissions on all documents in a SharePoint Online document library:

#Connect to SharePoint Online Site
$SiteURL = "https://yourdomain.sharepoint.com/sites/sitename"
$UserName = "yourusername@yourdomain.com"
$Password = "yourpassword"
$SecurePassword = ConvertTo-SecureString $Password -AsPlainText -Force
$Cred = New-Object System.Management.Automation.PSCredential($UserName, $SecurePassword)

Connect-PnPOnline -Url $SiteURL -Credentials $Cred

#Set Variables
$ListName = "Documents"
$FolderPath = "/Shared Documents"

#Get all Documents from the document library
$Documents = Get-PnPListItem -List $ListName -Folder $FolderPath

#Loop through each document and reset permissions
foreach ($Doc in $Documents)
{
    Set-PnPListItemPermission -List $ListName -Identity $Doc.Id -InheritPermissions $true -ClearAllPermissions $true
}

Write-Host "Permissions reset complete."

You will need to replace the following placeholders with the appropriate values:

• https://yourdomain.sharepoint.com/sites/sitename - the URL of your SharePoint Online site
• yourusername@yourdomain.com - your username for the SharePoint Online site
• yourpassword - your password for the SharePoint Online site
• Documents - the name of your document library
• /Shared Documents - the path to the folder containing the documents that you want to reset permissions for

Once you have updated the placeholders with the appropriate values, save the script as a .ps1 file and run it in PowerShell. The script will loop through each document in the specified folder and reset the permissions to inherit from the parent folder.