Cannot add Site Collection Admin as Global Admin using PowerShell in Office 365

Question

I'm a global admin in Office 365. I can use the SharePoint Admin Portal to update the site collection admins for existing sites.

However, if I try to do this in PowerShell using Set-SPOSite I get an error saying

I'm not the site collection administrator.

I have hundreds of test site collections that have been created by other global admins. It will be very tedious if I have to add myself as a site collection administrator to each of these through the admin portal.

Is there a way for a global administrator to take control of a site collection using PowerShell?

Answer 1

Below is a Powershell script to use in "SharePoint Online Management Shell" for adding site collection admins for ALL site collections:

$AdminLogin = "adminlogin"
$Sites = Get-SPOSite -Limit ALL

Foreach ($Site in $Sites)
{
    Set-SPOUser -site $Site.Url -LoginName $AdminLogin -IsSiteCollectionAdmin $True
}

Answer 2

You can remove site collection admin from All Site Collection and then add site collection admin to ALL SharePoint online site collection .

For remove site collection admin :

Import-Module Microsoft.Online.Sharepoint.PowerShell -DisableNameChecking



#Variables for processing

$AdminURL = "https://crescent-admin.sharepoint.com/"

$AdminAccount="[email protected]"



#Connect to SharePoint Online

Connect-SPOService -url $AdminURL -credential (Get-Credential)



#Get All Site Collections

$Sites = Get-SPOSite -Limit ALL



#Loop through each site and add site collection admin

Foreach ($Site in $Sites)

{

    Write-host "Scanning site:"$Site.Url -f Yellow

    #Get All Site Collection Administrators

    $Admins = Get-SPOUser -Site $site.Url | Where {$_.IsSiteAdmin -eq $true}



    #Iterate through each admin

    Foreach($Admin in $Admins)

    {

        #Check if the Admin Name matches

        If($Admin.LoginName -eq $AdminAccount)

        {

            #Remove Site collection Administrator

            Write-host "Removing Site Collection Admin from:"$Site.URL -f Green

            Set-SPOUser -site $Site -LoginName $AdminAccount -IsSiteCollectionAdmin $False

        }

    }

}

For Add site collection admin :

#Variables for processing

$AdminURL = "https://Crescent-admin.sharepoint.com/"

$AdminName = "[email protected]"



#User Names Password to connect 

$Password = Read-host -assecurestring "Enter Password for $AdminName"

$Credential = new-object -typename System.Management.Automation.PSCredential -argumentlist $AdminName, $Password



#Connect to SharePoint Online

Connect-SPOService -url $AdminURL -credential $Credential



$Sites = Get-SPOSite -Limit ALL



Foreach ($Site in $Sites)

{

    Write-host "Adding Site Collection Admin for:"$Site.URL

    Set-SPOUser -site $Site -LoginName $AdminName -IsSiteCollectionAdmin $True

}

Reference :

http://www.sharepointdiary.com/2017/02/sharepoint-online-remove-site-collection-administrator-using-powershell.html

http://www.sharepointdiary.com/2015/08/sharepoint-online-add-site-collection-administrator-using-powershell.html