Nero is a multimedia disk mastering suite. Nero can be used to create and edit disk image files, in addition to burning data onto optical media. Disk image files are large archive files that represent the exact structure of an optical disk. Nero uses a default proprietary format for storing disk images which ends in the file extension ".NRG." This format is not very compatible with other software, so most users prefer to use the non-proprietary ".ISO" format when saving or editing disk image files. Converting an NRG file to ISO using Nero should only take a few minutes
Click on "File" in the program toolbar, then click "Open."
Locate the .NRG file you wish to convert to .ISO using the file browsing window.
Highlight the desired file and click "OK" to open the NRG file in Nero.
Click on "File" in the program toolbar, then click "Save As."
Click on the drop-down toolbar labeled "File Type." Select ".ISO" from the list of available options.
Enter a file name for the converted .ISO file, then click "OK." You now have a functional copy of your selected .NRG file in the .ISO format.