A backup of a SharePoint Server 2010 or SharePoint Foundation 2010 server/farm using the Backup Exec SharePoint agent fails with this error:
Final error: 0xe0001702 - The object was not found, or could not be accessed. V-79-57344-5890
None of the files or subdirectories contained within will be backed up.
Backup Exec 2010 R3 uses trusts between a media server and its various Remote Agents. If that trust is broken or lost, this error can be seen with SharePoint backups. The trust can be lost if a server role changes, for example a stand-alone server is made into a CASO/MMS server or changed from that to a stand-alone server.
Re-establish the trust between the media server and the Remote Agent in question. To do this and be sure that the Remote Agent is running the current release that matches that of the media server, it might be best to remove the Remote Agent in question and push it back out from the media server.