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Joep 06-26-2007 02:49 PM

Re: memory stick problem creating folder or file
 
Possibly:

If is truly FAT12 or FAT16 (and NOT FAT32) you're dealing with a fixed
maximum number of root directory entries. This number is defined in the boot
sector. Now you may be tempted to just change that using a disk editor but
then you'll be overwriting data in the data area. + Your new root entries
may be overwritten at any time as the file system still thinks your root is
just x entries in size.

For FAT16 it is advised to maintain 512 entries (for compatibility reasons).
186 would be a weird number I have not seen before, but maybe there's more
files actually there in form of a bunch of hidden files in your root.

Anyway, all root dir entries used is the most plausible explanation I can
think of. Use something like Winhex to have a look at the boot sector to
determine the value. If you're a DOS fetishist you can also use our
DiskPatch.

--

Kind regards,
Joep - DIY DataRecovery.nl

http://www.diydatarecovery.nl

Important: When replying to this mail, please include previous
correspondence!

"Drew" <drew@drew.com> schreef in bericht
news:ju328395rdraoa50glt0fb0pdg9q79r70u@4ax.com...
>
> Hi All:
>
> I have a PNY 1 Gig memory stick that has always workedc great. Its
> formatted as FAT and was formatted this way from factory as I've never
> formatted it at all.
>
> I'm able to access all data on it with no problems and chkdsk reports
> no problems.
>
> In the root of the stick, I have 45 folders and 141 files.
>
> From the root, if I attempt to right click in Explorer and create a
> new folder or a new text file, I get: Unable to create the folder
> 'New Folder', The dcirectory or file cannot be created. Attempting to
> create a new text file gives a comparable error.
>
> However, if I go into any of the subfolders, I can create a new file
> or a folder within any of them with no problem.
>
> I just can't seem to add anything new to the root. Is there some
> limitation with FAT that could be causing this?
>
> Also, the memory stick is only using 452 MB with 509 MB free space
> remaining.
>
> Any help is appreciated!
>
> Drew
>
>




mhaase-at-springmind.com 07-04-2007 01:07 PM

Re: memory stick problem creating folder or file
 
On Tue, 26 Jun 2007 16:49:04 +0200, "Joep" <available@request.nl>
wrote:

>Possibly:
>
>If is truly FAT12 or FAT16 (and NOT FAT32) you're dealing with a fixed
>maximum number of root directory entries. This number is defined in the boot
>sector. Now you may be tempted to just change that using a disk editor but
>then you'll be overwriting data in the data area. + Your new root entries
>may be overwritten at any time as the file system still thinks your root is
>just x entries in size.
>
>For FAT16 it is advised to maintain 512 entries (for compatibility reasons).
>186 would be a weird number I have not seen before, but maybe there's more
>files actually there in form of a bunch of hidden files in your root.
>
>Anyway, all root dir entries used is the most plausible explanation I can
>think of. Use something like Winhex to have a look at the boot sector to
>determine the value. If you're a DOS fetishist you can also use our
>DiskPatch.



I'd second that suggestion. And re: 186 being a weird number - I
remember reading somewhere that long file names take up additional
entries, so the limit can be substantially lower than 512.

M



Joep 07-27-2007 09:05 PM

Re: memory stick problem creating folder or file
 
"mhaase-at-springmind.com" <mhaase-at-springmind.com@> schreef in bericht
news:fl6n831ua02d18ansqr9bv1vpbefg070th@4ax.com...
> On Tue, 26 Jun 2007 16:49:04 +0200, "Joep" <available@request.nl>
> wrote:
>
>>Possibly:
>>
>>If is truly FAT12 or FAT16 (and NOT FAT32) you're dealing with a fixed
>>maximum number of root directory entries. This number is defined in the
>>boot
>>sector. Now you may be tempted to just change that using a disk editor but
>>then you'll be overwriting data in the data area. + Your new root entries
>>may be overwritten at any time as the file system still thinks your root
>>is
>>just x entries in size.
>>
>>For FAT16 it is advised to maintain 512 entries (for compatibility
>>reasons).
>>186 would be a weird number I have not seen before, but maybe there's more
>>files actually there in form of a bunch of hidden files in your root.
>>
>>Anyway, all root dir entries used is the most plausible explanation I can
>>think of. Use something like Winhex to have a look at the boot sector to
>>determine the value. If you're a DOS fetishist you can also use our
>>DiskPatch.

>
>
> I'd second that suggestion. And re: 186 being a weird number - I
> remember reading somewhere that long file names take up additional
> entries, so the limit can be substantially lower than 512.
>
> M


Of course you're right, that's it - stupid of me, it has been a while since
I actually wrote code to parse directory structures. Indeed long filenames
occupy directory entries and depending on the lenght of the long filename
they often even use multiple directory entries. So with only room for 512
entries for the FAT16 file system this space is used up pretty quickly.

BTW PartitionMagic has been able for a long time to increase the size of the
root.
--

Kind regards,
Joep - DIY DataRecovery.nl

http://www.diydatarecovery.nl

Important: When replying to this mail, please include previous
correspondence!




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