The Access XPA module is likely not installed on the workstation.
To verify, open Control Panel, Programs and Features and check for XPA in the list.
If XPA is present, run a Repair.
If XPA is not listed, install the XPA module on the workstation.
XPA: Error: 'Could not load file or assembly 'APS.XPA.Ledger' or one of its dependencies. The system cannot find the file specified'
Error occurs when trying to open XPA.