Check if Symantec Private Branch Exchance Service is running.
Start if this is not running.
If it is running, open cmd (Run as Administrator if UAC is not disabled), cd to <install-path>\veritas\netbackup\bin.
Run:
bpps
copy the text in the output and paste here.
NBU processes are covered in Appendix A of NetBackup Troubleshooting Guide
You will find a process flow diagram and explanation of what each process does.
In short: nbemm is the process controlling the NBU relational database.
vmd is the Volume Manager service that is necessary to configure devices.
