https://support.quest.com/kb/4044159/exchange-apm-4-5-17-exchange-backups-fail-after-upgrade-
Exchange APM 4.5.17 - Exchange Backups fail after upgrade. (4044159)
After upgrade to Exchange APM 4.5.17, backups fail and the NVBU Service stops running when a backup is attempted. 4044159
after upgradeexchangeapmbackupsfail