Open An Elevated Command Prompt
Click Start -> All Programs -> Accessories and right-click on Command Prompt. Select Run As Administrator. Of course, you need to be able to authenticate as the administrator on the PC you’re using.
Partitioning The Disk
Type:DISKPART
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This will open up the partitioning application. Next, type:
LIST DISKFigure out which of the drives listed is your USB drive, and note the number. It’s crucial you get this right, or you’re going to end up losing data on other drives.
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Next, type the following series of commands, but replace the DISK number in the first line with the appropriate number from the above list. Here, my disk is number 1. Don’t confuse this with PARTITION 1. That number should not change, even if your disk is 3.
SELECT DISK 1 CLEAN CREATE PARTITION PRIMARY SELECT PARTITION 1 ACTIVE FORMAT FS=NTFS ASSIGN EXIT
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Make It Bootable!
The format step may take a little while (it actually took about 30 minutes on my machine). When you’re done, put in your installation DVD if you haven’t already. Note down which drive letter your USB disk and Windows installation DVD are located at.
Go back to your command prompt and type – assuming D: is your DVD drive with the install DVD, and U: is your USB drive:
D:/BOOT/BOOTSECT.EXE /NT60 U:This will basically make your USB drive bootable.
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Copy Everything
The final step can be done from My Computer. Just open up the installation DVD, highlight everything, and drag it over to your USB drive.
This will also take a while.
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Now you should be all set – just insert the USB disk into your new PC, and enter the BIOS to adjust the boot order, or choose the option during start up which says Choose Boot Device.