Fujitsu ScanSnap Advanced Operation Manual page 125

Setting Passwords for PDF Files
3.
Click the [OK] button to close all open windows.
ATTENTION
It is not possible to open a PDF file if you forget the password.
HINT
The following characters can be used to set passwords:
l Max. characters: Up to 16 characters
l Alphanumeric characters: A to Z, a to z, 0 to 9
l Symbols: ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \ ] ^ _ ` { | } ~
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