In the Inventory Manager, all QR/Bar code is identified by #LS prefix. First of all, the QR/Bar code reader should be configured to add this prefix when reading a QR/Bar code. 
How to Set up the #LS Prefix for your Scanner.
Make sure your keyboard layout is set to US English, otherwise, QR code and barcode scanning will not work properly inside the Inventory module.
To configure the prefix, follow the instructions in the following Setup Guides:
Overview
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