I dont think that an update could cause the problem. It might make the problem known.
Download and run windirstat, lets see what on that drive, now. WinDirStat - Windows Directory Statistics
If you only have one drive or several that can be explained. Download a few updates at at time. Before each time you update make a system restore point. Then test the update, of no problem, add a few more after another restore point.
If the update is a problem, remove the update with the System restore and slowly install the others using the same method. System Restore - How to