Go to the NetVault Console - Job Management - Right click on the job in question and select "View Log".
You will see various colored circles on the left hand side and some of them will have an exclamation mark within the colored circle. This indicates that there is some additional information that needs to be viewed.
Double click the exclamation mark in the yellow circle against the "X items and their contents could not be backed up" warning message and this will open another window with the relevant items.
