This problem arose when investigating poor performance on an SBS 2008 server. The performance tab of the server in task manager was showing almost 100% utilisation of the processors but when sitching to the process tab I noticed something strange. The CPU utilisation column was missing !!
Stopping and restarting the app made no difference. Checking in the view columns selected and disable and re-enabling similarly had no impact on the problem. Without being able to see the percentage of cpu per process it was going to be a bit harder figuring out what was amiss. The initial colution was to install Process Explorer from Sysinternals from here – this allowed me to find the offending article – in this case a sql instance caught in a loop after a failed backup exec backup. Dealing with that cured the performance issue but lef the question of what caused the missing column and what to do to get it back.
The solution was to click on each of the tabs – starting with users at the right hand side back to the process tab – and lo the column reappeared.