Event ID 1088Error from the WS-Trust (federation) endpoint

What to check

Check the federation server's WS-Trust endpoints and that no proxy is altering the response.

Find it with PowerShell

Run on the machine that logs it.

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2Get-WinEvent -FilterHashtable @{ LogName = 'Microsoft-Windows-AAD/Operational'; Id = 1088 } -MaxEvents 50 |
    Format-List TimeCreated, Id, Message

Hunt for it in Sentinel or Log Analytics

This works once a data collection rule sends the Microsoft-Windows-AAD/Operational log to your workspace, where it lands in the Event table.

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5Event
| where TimeGenerated > ago(7d)
| where EventLog == "Microsoft-Windows-AAD/Operational" and EventID == 1088
| project TimeGenerated, Computer, Source, RenderedDescription
| order by TimeGenerated desc

Related Primary Refresh Token events

• Event ID 1006: PRT acquisition started
• Event ID 1007: PRT acquisition finished (final error code)
• Event ID 1081: Error from the Microsoft Entra authentication service
• Event ID 1084: Network error reaching an endpoint
• Event ID 1022: URL being accessed
• Event ID 1144: UPN provided for sign-in
• Event ID 1098: Token broker operation failed (0xCAA5001C)

Search all 123 event IDs →