• Cannot power on a virtual machine
• Powering on a virtual machine fails
• You see the error:
  
  An unexpected error was received from the ESX host while powering on VM VM_name.
  Could not power on VM : Reason
  Failed to power on VM.
  Failed to extend swap file from 0 KB to size KB.
  
  For example:
  
• • An unexpected error was received from the ESX host while powering on VM vm-124.
    Failed to power on VM.
    Could not power on VM : No space left on device.
    Failed to extend swap file from 0 KB to 1048576 KB.
    
  • An unexpected error was received from the ESX host while powering on VM vm-49.
    Failed to power on VM.
    Could not power on VM : Invalid metadata.
    Failed to extend swap file from 0 KB to 2097152 KB.

• To work around this issue when you see the Invalid metadata error, try one of these options:
  
  
  • Configure the ESX host to create the swap file on another datastore. For more information, see Storing a virtual machine swap file in a location other than the default (1004082).
  • Create a memory reservation with the same size as the memory assigned to the virtual machine. This prevents the creation of a swap file. For more information, see the Resource Management Guide.

Note: These work arounds allow you to power on the virtual machine. However, you still need to investigate the underlying storage issue.

• To workaround this issue when you see the No space left on device error, try one of these options:
  
  
  • Configure the ESX host to create the swap file on another datastore. For more information, see Storing a virtual machine swap file in a location other than the default (1004082).
  • Create a memory reservation with the same size as the memory assigned to the virtual machine. This prevents the creation of a swap file. For more information, see the Resource Management Guide.
  • Increase the size of the datastore on which the virtual machine is located. For more information, see the Increase a VMFS Datastore section in the vSphere Storage guide.

• This article is updated regularly with other reasons that may cause this issue. Check this article for updates.
• If you see a different reason for the failure, open a support request with VMware Support. For more information, see Filing a Support Request in Customer Connect (2006985).