Hi @Hanamichi Sakuragi ,
Is your Search Application Topology working fine in your SharePoint farm like below?
Also, what “opening any pages on search” in your post means? Could you give me a sample screenshot?
Anyway, I suggest you to start/restart Claims to Windows Token Service firstly:
Go to Central Administration -> System Settings -> Claims to Windows Token Service -> Enable Auto Provision(If it has been enabled, disable it and then enable it again):
Make sure the status of C2WTS is Started in Manage services on server:
If the error still exists, then you could check your ULS Logs to trace more information:
You can find Log path in Central Administration -> Monitoring -> Configure diagnostic logging:
I hope this information has been useful, please let me know if you still need assistance.
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