Drive not showing in File Explorer after "net use" command

I am running Windows 8 64bit and running Hyper-V VM's. On my host machine I want to map a drive to the VM using the following command.

net use * \\10.10.18.104\c$
Drive Y: is now connected to \\10.10.18.104\c$.

When I look in File Explore I don't see a Y: drive.

However, in the command window I can change directories using these commands.

Y:
dir

and all the files are displayed. Why does this not show up in File Explorer?

This seems to be intermittent as some days the drive does show up in File Explorer.

Thanks for the help

I'm going to venture a guess that you're running the command prompt as another user or as "Administrator" and you have UAC enabled. When this happens, you've mapped the drive under a different user context than the one your Explorer window is running in. Launch a command prompt without doing Run As Administrator or Run As a Different User and you should be fine.