@Terry N
Yes, you are right.
By design, when a user exceeding usage limits or making too many requests within a single time, SharePoint will return "429 TOO MANY REQUESTS" error. It means SharePoint Online enforce Throttling limits function, in order to preserve service health.
You could refer to this article Avoid getting throttled or blocked in SharePoint Online to view more information.
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@Terry N
……………… Updated Answer ………………
Enforcing limits scope:
- 10,000 SharePoint groups per site (site collection).
- Each SharePoint group can have up to 5,000 users.
- 5,000 role assignments per uniquely permissioned item.
Because users of the “Everyone except external users” group exceeds 5000 in your SharePoint Online. I suggest you could split "Everyone except external users" group into several groups. You can follow these steps:
1.You can group internal external by Departments, such as "Sales Dep", "Personnel Dep", "Finance Dep", etc.
2.Add users in the "Everyone except external users" group to the corresponding group.
3.Use these groups to replace the "Everyone except external users" group.
4.You could run the following commands in the SharePoint Online Management Shell as an admin:
$admin = "username@aabc.onmicrosoft.com"
$password = "****"
$cred = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist $admin, $(convertto-securestring $Password -asplaintext -force)
Connect-SPOService -Url https://aabc-admin.sharepoint.com -Credential $cred
$SiteURL= "https://aabc.sharepoint.com/sites/test1"
Get-SPOUser -Site $SiteUrl -Limit All | select DisplayName,LoginName,IsSiteAdmin,IsGroup,@{n="Groups";e={$_.Groups -join ";"}} | Export-Csv "D:\report.csv"
Thanks,
Echo Du
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