With Nero Burning ROM you can save a data disc as an image file. The image file can later be burned to a recordable disc. The result is a copy of the original data disc.  
To save the data disc as an image file, proceed as follows:
1.
Insert the data disc in a drive.
2.
Click the Extras > Save data tracks menu.
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The Select Track window is opened. The tracklist shows you the sessions and data tracks that are found on the disc. Due to the technical reasons, only the first data track of the first session can be saved.
3.
Select the first data track.
4.
Click the Save Track button.
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The Save As window is opened.
5.
Select a file name and a storage location.
6.
In the Save As drop-down menu, select the desired output format (ISO or NRG) for the image file. 
7.
Click the Start button.
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The Progress window is opened and displays the progress made while saving. When the save process is complete, the window is closed automatically.
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You have successfully created an image file starting from a data disc. Now you can burn the image file to a disc.

Saving Data Track