Microsoft Excel runs in a macOS sandbox, it can’t access files in all locations when used with Devart ODBC Driver for xBase.
When a sandboxed application starts for the first time, macOS creates a dedicated container for it in ~/Library/Containers. The application has full read and write access only within its own container.
To allow Microsoft Excel to open the database files, place them in the following directory: /Users/user_name/Library/Containers/com.microsoft.Excel/Data/Documents/. Replace user_name with your current macOS account name.