The volume snapshot driver has completed processing for volume offline. Volume GUID: %1 Guidance: When a volume is taken ...

The volume snapshot driver has completed processing for volume offline.

Volume GUID: %1

Guidance:
When a volume is taken offline, the volume snapshot driver disables any persistent snapshots that still exist for the volume (autorelease snapshots were deleted when the volume was dismounted).  Snapshots of other volumes whose diff areas are on the offlining volume are destroyed, unless those volumes are in snapshot protection mode.  In that case those volumes are taken offline.

You should expect this event when a volume is taken offline.  No user action is required.