create a bootable file from a DVD or USB flash drive from Windows 7 USB/DVD download tool 1. Please download (Free) and install Windows 7 USB/DVD download tool from Microsoftstore.com or codeplex.com
2. format your USB Drive with NTFS
3. Run Windows 7 USB/DVD download tool
3.Select you ISO file
4. Select you destination USB that you would like create bootable USB Drive
5. Wait
6. And wait until complete
7. then you will have bootable USB drive to install your Windows server 2012
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