query on onedrive

Hi @Roger Roger ,

Welcome to Q&A forum!

If you want to get how many users have access to User 1's OneDrive:

First, you need to add yourself as an administrator of User 1's OneDrive.

https://www.sharepointdiary.com/2017/04/gain-admin-permission-to-onedrive-for-business-sites-using-powershell.html

Non-official, just for reference.

Then, you can get the Sharing report in User 1's OneDrive.

Open User1's OneDrive, go to OneDrive settings--More Settings--Run sharing report, and you'll be asked where in the drive you want to save the report. The resulting csv file shows the different ways a file has been shared and with whom.

https://www.ytria.com/blog/onedrive-sharing-report-for-all-users/

Non-official, just for reference.

Finally, if you want to terminate sharing in batches, you can use PowerShell to remove the sharing link.

Function Remove-OneDriveSharingLink {
    param (   
        $OneDriveURL
        )   
    process {
        Connect-PnPOnline -Url $OneDriveURL 
        $Ctx= Get-PnPContext

        $Files= Get-PnPListItem -List "documents"
        foreach( $File in $Files) {       
            $Froles= $File.RoleAssignments
            $Ctx.load($Froles)
            $Ctx.ExecuteQuery()

            If($Froles.Count -gt 0) {
                for ($i = $Froles.Count -1; $i -ge 0 ; --$i){   
                $Link=$Froles[$i].Member
                $Ctx.Load($Link)
                $Ctx.ExecuteQuery()
                If($Link.title -like "SharingLinks*") {
                    $Froles[$i].DeleteObject()
                }
                $Link = $null
            }
            $Ctx.ExecuteQuery()           
            }      
        }
    }
}

Remove-OneDriveSharingLink -OneDriveURL "https://<tenant>-my.sharepoint.com/personal/<username>_<tenant>_onmicrosoft_com"

It breaks all the links shared, internal or external.

For more info., please see:

https://sharepoint.stackexchange.com/questions/278316/how-can-unshare-stop-sharing-of-onedrive-files-and-folders-using-powershell

The PowerShell command you use to grant User 2 access to User 1's OneDrive is completely correct. The premise is that you have administrator privileges to User 1's OneDrive.

For your references:

https://zcusa.951200.xyz/en-us/microsoft-365/admin/add-users/remove-former-employee-step-5?view=o365-worldwide#access-a-former-users-onedrive-documents

https://techcommunity.microsoft.com/discussions/onedriveforbusiness/onedrive-external-sharing-and-departed-users/130931

Good day!

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Here is a free and open source app that help you out to generate a report of all permissions in a Site/OneDrive.

https://github.com/Barbarur/NovaPoint

This is the documentation about the permissions report; https://github.com/Barbarur/NovaPoint/wiki/Solution-Report-PermissionsReport