I\'m running PowerShell in a Windows 7 x64 virtual machine. I have a shared folder on the host mapped as a network drive (Z:). When I run PS normally I can access that drive
In the end the fix was simply to re-map the drive letter while running as Administrator:
net use Z: "\\vmware-host\Shared Folders"
It doesn't have to be done from the same PowerShell instance (or from PowerShell at all) - it's just something that needs to be done once for the entire logon session.