Make sure you are using the latest version of PowerShell. On Windows 8/10 run it as administrator and type the following:
New-PSDrive –Name “Z” –PSProvider FileSystem –Root “\\fileserver01\share” –Persist
Z – is the Drive Letter
Within ” ” is the path of the network share that will be presented as the root of the drive letter Z
The -Persist parameter so that you can not only see the name of your new drive in Windows explorer, but also know it’s still there the next time you logon.
Specifies a name for the new drive. For persistent mapped network drives, type a drive letter. For temporary drives type you are not limited to drive letters.
Specifies the Windows PowerShell provider, for example, FileType or Registry.
Specifies the data store location, for example, \\Server\Drivers, or a registry key such as HKLM:\Software\Microsoft\Windows NT\CurrentVersion.