networking - Windows server, temporary alias name, only visible from one machine

Two weeks ago our IT department migrated a huge network folder from an older server to a newer one. For example, the older folder was reachable under

 \\oldserver\ourfolder

and the new one under

 \\newserver\ourfolder

Note the old server is still in use and visible in our companies network, \\oldserver\ourfolder was archived in between and deleted from the server.

Now we found out that there are several files (actually CAD files in some proprietary binary format) having hardcoded references pointing to the old folder location. Since there are several of those files, we would like to write a program to change those references to the new location. Unfortunately, the CAD system's VBA interpreter will only allow this when the referenced files are visible under the old network path. Otherwise, it will stop execution with an error message

So what we need here is a way to make "oldserver" an alias name for "newserver". This should be done only temporary, and only for one machine (a Windows 7 client), so our first idea was to use the hosts and lmhosts files for this. But this apparently does not work. We added a line of the form

    oldserver

to the hosts file and

    oldserver #PRE

to the lmhosts file. ping oldserver then shows the new IP address, but this does not have any effect on the shared network folders, for example, displayed by the Windows explorer, or other applications like our CAD application.

Second thing we tried was to setup an isolated DNS server on the local machine with the old server pointing to the IP address of the new one, and using "127.0.0.1" as preferred DNS (and no, we did not forget to flush the DNS cache by ipconfig /flushdns). After this, nslookup oldserver shows the expected IP address of the new server, but Windows Explorer still sees the old server under its name.

I guess this has something to do with WINS and how NetBIOS name resolution works, but I have no clue what I could try else.

Note this is about the way one client sees the network, so I think it must be possible not to change anything on the involved servers, only the client.