Encountering the following error while importing OVF template in vCenter?
Transfer failed: The OVF descriptor is not available
This is usually caused by file corruption. Either the source template is corrupted, or the corruption occurred in transit between the source and vCenter.
Try first reimporting again, if failing, check md5sum signature if available, re-export the source template to OVF (if you are the creator) and then re-import to vCenter.