Drive visible in File Explorer but inaccessible.
Windows Disk Management shows the disk as Unknown and Unallocated.
System Event Logs in the guest-OS shows "Warning: The IO operation at logical block address 0x0 for Disk <ID> (PDO name: \Device\####) was retried".
The Guest-OS fails to automatically re-initialize the disk or refresh the partition table after the underlying storage path was lost and subsequently restored. This results in the OS treating the disk as uninitialized or placing it in a Read-Only state likely to protect data integrity.
Note: Ensure the VM has backups before proceeding.
1. After the storage LUN had been re-mapped, ensure the datastore files can be browsed from host client or esxcli, and there are no errors related to the affected storage LUN in the host logs.
2. If the datastore is not visible in the host, perform a rescan of the storage on an ESXi host.
3. In the guest-OS, Use "Rescan Disks" option in Disk Management in an attempt to bring the affected disk to online state. To rescan disks, open disk management utility, under the "Action" menu select "Rescan Disks".
4. Restart "Virtual Disk" service: On windows OS, open services, locate the Virtual Disk service. Right-click on the virtual disk service and select Restart. If the service is stopped, click Start.
5. If the above steps do not solve the issue, perform a reboot of the virtual machine. This forces the virtual storage controllers to re-initialize and triggers a fresh scan of all mapped VMDKs/RDMs.