The database (Oracle/SQLServer) agents are alerting that a number of disk are full, for example from the DBSS - Disk Percentage Used rule. These disks are identified by names such as HardDiskVolumeX where X is a number
If the disk has a drive letter, the database agent will show the drive letter for the disk.
if the disk is configured in Disk Management in Windows but has no drive letter, the Agent will bring the windows default name for the disk. for example: HarddiskVolume2.
Identify the disk on the monitor host refused via the volume and reduce the space on it
Configure the disk with a drive letter