Task Manager does not show memory usage

I had the same problem. All that I had to do is:

1. Open Control Panel
2. Click Change keyboard or other input methods
3. Click Formats tab on top
4. Click Customize Formats/Additional Settings
5. Click Reset
6. Click Apply then OK
7. Restart Computer

Now after restart try opening Task Manager and see if helped. This resetting solved the exact same problem for me.

Open Task Manager

Go to processes Tab

View -> Select Colums

Select Memory

It's from regional settings. I had Romanian, after installing something it no longer showed the amount, just K; I switched to English (US), it worked; I switched then back to Romanian and it is still working.