If WebDAV is configured for NVSD, but not working properly for NVBU, backups to NVSD will fail with errors similar to:
Error while closing the backup stream
Failed when finalizing the backup
Job manager lost message channel unexpectedly
Only NetVault Backup 8.6.1+ installations have the necessary coding to handle the WebDAV authentication credentials required for the handshake with the SmartDisk 1.5.1+. So even though your NVBU Server is running 8.6.1+ with proper WebDAV credentials configured, backups of pre-8.6.1 Client machines will fail immediately, as they ignore the WebDAV credentials for SmartDisk that they are passed by your NVBU 8.6.1+ Server.
Upgrading all of your NVBU Client machines to a minimum of 8.6.1 will allow those clients to successfully obtain and use the WebDAV credentials necessary for authenticating with SmartDisk 1.5.1+ from the NVBU 8.6.1+ Server.
