Please confirm you are running version 18.104.22.1683 prior to installing this hotfix. You can check this under Help | About in Veeam Backup & Replication console.
Prior to installing this hot-fix please reboot the Veeam server to clear any locks on the Veeam services and when the reboot is done, please stop all the Veeam services and apply the hot-fix.
After installing the hotfix, start the Veeam services.
MD5 for the Veeam.Backup.Core.dll: eb7ac7df245050b86f0dc5ab13e002a0