I think your problem is that you are not able to create directory with the above code in some computers.... I had checked the above code and is working....
But you had mentioned that in some computers, you are not able to open the C drive with double click... and you need to open it using the popup menu....
I think, this is the problem of that Windows.... Try reinstalling the windows.....
I don't know whether it will solve your problem... Or wait for what others can say about this....

Note: If you are not able to open the C drive using double click, try to ask this question on any forum that will answer on Windows problems...

Bye..