When the disk space is exhausted and a thin-provisioned disk cannot expand, the virtual machine cannot boot. If you created a virtual disk in the thin provision format, you can convert it to the thick provision format.

The thin provisioned disk starts small and at first, uses just as much storage space as it needs for its initial operations. After you convert the disk, it grows to its full capacity and occupies the entire datastore space provisioned to it during the disk’s creation.

For more information about thin provisioning and available disk formats, see the vSphere Storage documentation.


  1. Verify that the disk format of a virtual hard disk is Thin Provision.
    1. Right-click a virtual machine and click Edit Settings.
    2. On the Virtual Hardware tab, expand Hard disk and check the Type field.
    3. To exit the wizard, click Cancel.
  2. To open the datastore management panel, click the Datastores tab, and click a datastore from the list.
    The datastore that stores the virtual machine files is listed.
  3. Click the Files tab, and open the virtual machine folder.
  4. Browse to the virtual disk file that you want to convert.
    The file has the .vmdk extension.
  5. To convert the virtual disk to a thick provision format, click the virtual disk file and click the Inflate icon.


The inflated virtual disk occupies the entire datastore space originally provisioned to it.