vRanger backups to SmartDisk fail with: "Failed to acquire the shared resources. Unable to connec (4046232)

Any attempt to backup or restore to/from SmartDisk or creating a SmartDisk repository will fail with the above vRanger error.

Verifying the SmartDisk status, shows it is started with the "percolator slave" process listening.
"smartdisk.bat stats" or "smartdisk.bat config --show" return normal outputs.
Testing SmartDisk access and webdav authentication via web browser (http://<localhost_IP>:<port>/proc/dedupe/stats.stnz) works as expected, pointing to a vRanger issue rather than SmartDisk.

Note: In this particular instance, vRanger and SmartDisk are both installed on the same physical machine, which is not supported as per the vRanger/NVSD Integration guide:
As per http://us-downloads.quest.com/Repository/support.quest.com/vRanger/5.5/Documentation/E/vRanger_5.5_NVSDIntegration.pdf"