When I am opening task manager, I am not been able to see the corresponding network utilization for each process in Process tab, though I am able to see the network usage in Performance tab of the task manager. I am attaching screenshots.
Are you running as administrator? I don't remember how is done in Windows 8++. But in Windows 7, after you open the TaskManager, then you go to Process and select "show process of all users". You will prompted by the UAC, and if you accept it, then the TaskManager is running as administrator. You could not using the network at all at the time you looked, or must be another process, running with other users, a system user - totally normal! - and so it is not shown to you. cheers
The problem is not solved by running as an administrator, actually I was getting the Network Utilization for each process the normal way, but what I suspect is something broke after the Windows Update and since then it is not shown.
I don't know. Try sfc /scannow in a CMD as Administrator, then! Maybe you need to reboot, maybe you need to do more than one time, maybe you need to run in safety mode. But, I don't know. This is what I run when I suspect that system files are corrupt. cheers