Policy
Set document synchronization timeout
This policy setting specifies the server timeout value in milliseconds for document synchronization. This policy setting does not apply when synchronizing documents on SharePoint servers. If you enable this policy setting, you may specify the server timeout value in milliseconds for document synchronization. If you disable or do not configure this policy setting, the server timeout will default to the Windows timeout value.
1239d3954e1fL_SetDocumentSynchronizationTimeoutRegistry
Copy registry mappings
HKCU\software\policies\microsoft\office\16.0\common\internet\documentsynctimeoutPolicy notes
This policy setting specifies the server timeout value in milliseconds for document synchronization. This policy setting does not apply when synchronizing documents on SharePoint servers. If you enable this policy setting, you may specify the server timeout value in milliseconds for document synchronization. If you disable or do not configure this policy setting, the server timeout will default to the Windows timeout value.