Requires:

First of all, install Nero and prepare your Installation source files by copying them to particular folder or directory. Lets say- all files are copied to C:\DVD folder.
Start Nero Burning ROM (Go to Start >> All Programs >> Nero >> Nero 9 and click on Nero Burning ROM). On New Compilation dialog box, Select DVD as compilation and then DVD-ROM (Boot).

On Boot tab and locate boot image file using Browse button. (Windows Vista and Windows 7 installation source contain boot image file called etfsboot.com in Boot directory) See the above image.
Windows Vista x64 Installation files doesn’t contain etfsboot.com, so you can use the same file from x86 version.
Now under Advanced, check Enable expert settings (for advanced users only), set emulation type as No Emulation & number of loaded sectors as 8 and leave rest of settings intact. (1 sector = 512Bytes, etfsboot.com requires 4.0KB to boot DVD)
On ISO tab, select File name length as Max. of 31 chars (Level 2). Now move Label tab and set the label of disc, say “Windows 7 DVD”.

On Burn tab, don’t forget to check Finalize the disc (No further writing possible!). Now almost everything is done, so click on New to add Windows 7 Installation Source files.

Just select all files and folders from DVD and drag them under to Windows 7 DVD. That’s it, now click on Burn button on toolbar or choose Recorder menu >> Burn Compilation. Insert the blank DVD into drive and set appropriate burning speed. It is recommended to burn disc lower speed (2x or 2.4x) for better results.

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