This is not a typical problem. Usually it works or it doesn’t.
It’s possible that your firmware update changed the USB setting. Go to Settings/System Settings/USB Mode and change it to MSC and try the copy…
It’s also posslble you have a bad cord. If there’s only an intermittent connection in the cord, you could get disconnects.
Finally, it’s possible you are reaching some limit on memory use in your computer for the large file. Windows may be trying to put it in some temporary cache before sending it over, and that cache doesn’t get full with a small file but does with a larger one.
Just for an experiment, disconnect from the internet and then turn off your antivirus program, which can hog a lot of memory, and try the copy. Obviously you need antivirus, so that’s not a permanent solution.
But if it helps, it means you have too many things running in the background. You can look at all of them by pushing CTRL-ALT-DELETE once to bring up Task Manager. Look at Applications and look at Processes, which shows you everything running. Look under Memory Usage to see if there’s anything that’s gobbling up memory.
