OK, but why do you think it's WinSCP issue? Do you see the Z: drive in any other SFTP client?
I will explain briefly,
We installed OpenSSH Server in our one of the VM called VM1. In that VM1 already exist drive "C" and "D" but we created one Mapped Drive called "Z".
Then we installed WinSCP Client in our one of the VM called VM2. In that VM2 going to run WinSCP Client and we can able to login OpenSSH server help of session login window. Now we are going select root option from Remote File Panel. Here we able to see only "C" and "D" drive but "Z" drive not showing. Please refer attached screen shot.( Highlighted Yellow color).
Kindly review and update.
We have requirement to access server Mapped Network Drive on WinSCP client Remote Directory Panel.
We tired but it not showing.
Please anyone help on this.