I made many windows 10 updates on my workstations lately. And since then, some computer remain blocked for up to several hours on the "Application of the Microsoft Offline files strategy". For the past 2 weeks, I have been notified of a few dozen affected posts in my IT stock, some have only blocked once, others keep doing it every day. The only way I have found to troubleshoot them is to reboot the PC once after having moved it to a no GPO OU, then put it back in the original OU. But on several computers, it has no effect. The problem comes back several times a year since I created the domain. We use local sessions with document redirection (with Koxo software), and SSO connection to Office365.
On the workstations concerned, I noted this message in the Windows log:
The processing of the notification event (CreateSession) by the Winlogon notification subscriber <GPClient> took 3596 seconds.