By default the Windows Client mounts the cloud drive with the letter M.
If you wish to change the drive letter for all the users, log in on the web portal with an Admin account. Go to the Group Policy->Client Control->Client Settings Manager page. Then, select another letter from the drop-down menu and save.
This setting can be applied at either the Cluster level (all Tenants), or at a Tenant level. If you wish to set it for a single Tenant, open the Tenant Dashboard and access the group policy page. For the Cluster, go to the Default Group Policy page from the hamburger menu->left-panel navigation.
The Windows Clients will display the new letter after they are restarted.
Screenshot of the Group Policy->Client Settings Manager page for the Cluster:
To change the drive letter for a single user, you can change the drive letter from the native or web management console of the Windows Client. Both options are accessible from the Windows Client menu in the Windows Taskbar.
As mentioned previously, this setting only takes effect after the Windows Client is restarted.
Notice: When the Windows Client can't use the assigned drive letter due to a conflict, it will use the next available drive letter automatically.