Windows 7 - Mapped drives

We have a linux server and all the Windows 7 Pro workstations have the same mapped drives, w,x,y,z. The only problem is that the path for z is a share nested in another share, w. When we try to map z we get the message, 'Multiple connections to a server or shared resource by the same user, using more than one user name, are not allowed. Disconnect all previous connection to the server or shared resource and try again.'

How can we work around this? These drive maps mus remain the same as the server is set up by our software vendor.

The link below talks about the problem and mentions using the IP address to access the server instead.

Multiple connections to a server or shared resource by the same user, using more than one user name, are not allowed...

Using method 1 in the link below seems to work the best.
Error message when you use user credentials to connect to a network share from a Windows-based computer: "The network folder specified is currently mapped using a different user name and password"