🤔 Problem
A SharePoint Agent connected to SharePoint Online fails with the following error:
Error running agent: [500] Could not execute the specified command: Cannot extract required information from IDCRL header. Header=, IdcrlType=, ServicePolicy=, ServiceTarget=, Endpoint= InnerException:HTTP protocol error. 403 Forbidden.
🌱 Solution
Microsoft is retiring IDCRL (Identity Client Runtime Library)–based authentication for SharePoint Online on . See Legacy SharePoint Authentication (IDCRL) Is Retiring — What to Do Before May 1, 2026 | Microsoft Community Hub
To resolve this, perform the following steps:
-
Upgrade to PeopleSync 26.4 or newer. You can download the current version here:
https://www.messageconcept.com/downloads/peoplesync/PeopleSync_Setup.zip -
Change the SharePoint Agent to use an Entra ID App Certificate.
We have provided a migration guide that is contained in the download package of PeopleSync 26.4 and higher.