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When you installed your RBS Server you selected a root data folder to contain your client's backup files.

By default the folder is C:\RBS\ but is most often changed to another drive.

If the root folder becomes inaccessible, the RBS Server will stop running and may exhibit strange behavior.

The Root Folder can become inaccessible if it is on a network drive, or a USB drive that has become disconnected or unmounted.

The most common cause of this problem is an accidentally disconnected data drive.

Reconnect the drive with its original drive letter mapping and restart the RBS Server.