Step 1: Download Nokia DRM Removal, install and launch it. And then click 'Add...' to add files that need to be converted. You are allowed to add a folder or import DRM files from the appointed folder through DRM Finder.
Step 2: Choose an output format from 'Convert audio to' or 'Convert video to'. Then click the 'Settings' button to set the video parameters (such as resolution, frame bite, encoder, and bit rate) or audio parameters (such as sample rate, channel, encoder and bit rate, etc ) if you have higher requirement for the output quality. Then click 'Browse' button to set the destination folder for saving output file.
Step 3: After that, click 'Start' button at the lower-right on the main window, conversion will soon be done. Then you can freely share or transfer songs to your Nokia without any restriction!
Read Guide: How to Remove DRM from M4B iTunes Audiobook?