Unable to copy files using windows 7 usb/dvd download tool

Finally i found the solution to my own post and here is the solution for it. I hope it will help some other user who are facing the same problem. 

Sometimes if your USB stick has something in its MBR you might get the error

Windows 7 USB/DVD Download Tool error: We were unable to copy your files. Please check your USB device and the selected ISO file and try again.

You have to start command prompt as an Administrator (On Windows 7 that means right clicking the cmd and selecting Run as Administrator) and use the diskpart utility.

WARNING: Be careful to select the right drive or else your day won’t have a happy end because if you select the wrong drive you will lose all your data on this drive!

Instead of formatting the partition with FAT32, you can also use NTFS (like WUDT does), but then you need an extra step to make the drive bootable:

Bootsect.exe /nt60 X:

“X:” is the drive letter of your USB stick. Bootsect.exe can be found on the Windows 7 DVD in the boot folder. However, I can’t really recommend using NTFS. Some USB stick, at least, appeared to be slower with NTFS.

1. Start command prompt as Administrator and type  diskpart
2. type  list disk
3. type select disk  and number of your USB disk ( like select disk 1 )
4. type  clean
5. type  create partition primary
6. type  select partition 1
7. type  active
8. type  format quick fs=fat32
9. type  assign
10. type exit  to exit the diskpart utility
11. type exit  to close command prompt

Finally Bootable USB device created successfully.

Thanks to everyone and i am glad it solved each ones problem.

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