DeviceLock Service : Managing DeviceLock Service for Windows : Service Options : Auditing & Shadowing : Prevent data transfer on errors
  
Prevent data transfer on errors
Enable this parameter to prevent users from transferring data when shadowing or content analysis is not possible. As a result, users will only be able to transfer data if the disk has sufficient space to store shadow copies and to save the data that is necessary for the normal functioning of Content-Aware Rules.
When the Prevent data transfer on errors parameter is enabled, the total size of the directory specified in Local storage directory reaches the quota specified in Local storage quota (%), and there is no data that can be deleted, the DeviceLock Service stops shadowing and content analysis, and blocks any user data transfer attempts.