Policy
Set UNC interval to poll for changes on file servers
This policy setting allows you to change the synchronization interval at which OneNote will poll for changes on the server. When OneNote synchronizes a notebook on UNC, also known as SMB or Windows File shares, OneNote will receive notifications from the file server as well as poll the server looking for new updates on the server. By making the interval faster it will make OneNote synchronize faster, but it also might cause performance issues on the server. If you enable this policy setting, you may specify the number of seconds OneNote will poll. If you disable or do not configure this policy setting, OneNote will automatically poll every 30 seconds.
fd5021c79380 L_SetUNCIntervalToPollForChangesOnFileServers Registry
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HKCU\software\policies\microsoft\office\16.0\onenote\options\save\folderpollintervalPolicy notes
This policy setting allows you to change the synchronization interval at which OneNote will poll for changes on the server. When OneNote synchronizes a notebook on UNC, also known as SMB or Windows File shares, OneNote will receive notifications from the file server as well as poll the server looking for new updates on the server. By making the interval faster it will make OneNote synchronize faster, but it also might cause performance issues on the server. If you enable this policy setting, you may specify the number of seconds OneNote will poll. If you disable or do not configure this policy setting, OneNote will automatically poll every 30 seconds.