The config.properties setting webdms.workspaceServer.showLocalDrives is not applicable to Single User Edition.
Here's a note from the SAS Studio 3.8 Single User Edition download page: "Use this download to add the Single-User Edition of SAS Studio 3.8 to your Windows desktop. SAS Studio should be installed on the same machine as Base SAS release 9.4M4 or later."
The screenshot indicates that you have SAS 9.4M1 installed, so you will need to use an earlier version of Single User edition.
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