The article applies to windows client/server agent 12.12.570.53288 and newer. To scan an attached folder in old windows client/server agent, check the article here.
In cases where a Windows Machine ends up in a state which prevents the Windows Client from syncing content from an attached folder, a sync scan task can be started to force sync any possible discrepancies.
From the System Tray, launch the CentreStack Windows Client.
Navigate to Attached Folders, and click on the stethoscope next to the attached folder name.
Once the scan finishes, click on the icon to view the off-sync content.
Once the scan completes, select Sync all Selected Items.