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I have a Transcend flash drive formatted as FAT32.

I tried to format it as NTFS, with allocation unit size as 64K.

After a few minutes, I got a message saying:

The format did not complete successfully.

If relevant, while on FAT32, the file system had some errors after my system crashed. I didn't scan the drive to fix the errors as that would take several hours and I intended to format it anyway (which I believe would fix the errors).

  • How can I format the drive as NTFS with 64K allocation unit size?
  • Do I need to scan and fix the FAT32 filesystem first?
  • Do I need to use some other program to change the filesystem?
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up vote 2 down vote accepted

Do I need to scan and fix the FAT32 filesystem first?

Errors on the previous filesystem are irrelevant by themselves.

However, there's a certain chance that the filesystem got corrupted because the flash drive went bad. The format that you're unable to complete a format supports that idea.

How can I format the drive as NTFS with 64K allocation unit size?

The allocation unit size shouldn't have anything to do with you're problem. If it wasn't supported, Windows wouldn't display it.

However, I wonder why you'd choose a cluster size this big. 4 KB is the recommended value for all volumes under 16 TB (source), so it should work well for all current flash drives. All that increasing the cluster size does is making little files consume more space...

Do I need to use some other program to change the filesystem?

The error has nothing to do with changing the filesystem.

However, there are occasions when a normal format fails, but a low level format still succeeds.

For USB flash drives, you can try HP's low level formatting tool. If that doesn't work either, your drive is probably irrecoverably damaged.

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@[Dennis] Thank you for your reply. So if the filesystem got corrupted what can I do to change my filesystem to NTFS? If I allow the scan of the filesystem to complete and fix the errors would that solve the problem? Thank you also for the 4KB recommendation. I read somewhere that a larger cluster size helps performance. Is this true? That's why I opted for 64K. I know that it is inefficient with space, but I thought it would help performance. – Zesty Dec 29 '12 at 1:12
You won't notice a difference in performance. As I said, it's likely your flash drive went bad and you need to replace it. Format doesn't care about the previous filesystem. You could try HP's low level formatting tool, but there's a good chance it won't help. – Dennis Dec 29 '12 at 2:59
Sorry for the late response. I finally tried the low-level formatting tool and it worked. Thanks, Dennis! – Zesty Jan 20 '13 at 19:56

The command (for reference) is FORMAT /FS:NTFS x:, to format to a different format which would erase all the files. You can also try the /Q switch to do a quick format, which may succeed sometimes. The reason it may succeed is because the quick format does not write over every sector, just the initial part of the disk to say what format the drive is now in. Both commands should be run from the Administrative Command Prompt for Vista or higher.

To access the Administrative Command Prompt:

  1. Click on Start
  2. Type cmd and press Ctrl+Shift+Enter
  3. If prompted, press the Yes or Continue button
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