Xerox Document Centre 420 User Manual page 339

Select [Dialling Digits
Reporting].
Select the preferred option.
Select [Save].
Xerox Document Centre 440/432/430/426/425/420 User Guide
Dialling Digits Reporting (DC440/432/430/425)
This default selects whether the first or the last 20 digits of a
telephone number are displayed on reports and headers.
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