The Backup Exec Server Service did not start. An internal error (-1) occurred in object 50.
The issue is seen when the Managed Backup Exec Server MBES product version is greater than the Central Admin Server (CAS) server. MBES version is 22.1 and CAS version is 22.0.
As per the Best practices for CAS/MBES Setup, In an existing CAS environment, upgrade the Central Administration server, and then upgrade the Managed Backup Exec Servers.
Backup Exec 22 Administrator's Guide (veritas.com)
To check the version of Backup Exec installed on the MBES Server, navigate to Backup Exec Installation Directory (Default: C:\Program Files\Veritas\Backup Exec), right click on beserver.exe, select Properties and select Details.
Backup Exec Build or Version Information:
Backup Exec 22: 22.0.1193.1009
Backup Exec 22.1: 22.0.1193.1338
To avoid the error message, ensure that the CAS Server Backup Exec version is upgraded first to 22.1 and then upgrade the MBES Server Backup Exec version to 22.1