Hello Ming Cheung,
Thank you for posting in Q&A forum.
Because folder redirection is user policy, you need to run gpupdate /force or sign out and sign in the user account to make folder redirection GPO refresh.
However, for several special user configuration GPO settings, such as folder redirection, drive map, script (logon script and logoff script) and disk quota, the user must sign out and sign in the user account again to refresh/apply these GPO settings.
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
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