See if this helps:
http://nayabrasools.blogspot.co.za/2013_07_01_archive.html?m=1
Solution:-
NetBackup LiveUpdate apparently only checks for the "LiveUpdateHost.hst" file in the C:\Program Files\Veritas\NetBackup folder on your LiveUpdate server no matter if NetBackup is installed on said server or not. NetBackup is not required to be installed on your LiveUpdate server, but apparently, it still looks for this file in that path. In our case, we used a separate media server as the LiveUpdate server. NetBackup is still installed on the D: drive of the media server, so to fix the issue, I just created the same folder structure \Program Files\Veritas\NetBackup on the C: drive and copied the file from D:\Program Files\Veritas\NetBackup to the newly created C:\Program Files\Veritas\NetBackup folder. That fixed the first issue in bold above.
The 2nd issue in bold resulted from not having the upgrade packages unzipped correctly in the source folder on my LiveUpdate server. The documentation states that you need to unzip the files into the source folder, but it doesn't state that ALL files from ALL packages need to be unzipped into the SAME folder. I unzipped each one individually, which created a subfolder under the source folder, and the files resided under each subfolder. I had to move ALL of the files from each package's subfolder to the same source folder.
For example, if you have a source folder called C:\LiveUpdate and you unzip the package files for 32bit and 64bit Windows clients, you might end up with a "C:\LiveUpdate\32bit-client" folder and "C:\LiveUpdate\64bit-client" folder, with files from each package in their respective subfolders. You have to move the files under "32bit-client" to directly under C:\LiveUpdate, and the same for the files under "64bit-client" folder.