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Fixed your corrupted USB flash drive

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Fragrance

Fragrance

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Dear Friends

For whole benefit Couple of day’s back I bought a USB pen drive or flash memory which was unfortunately a fake drive, for those who never knows what is fake pen drive I explain here for our valued members and friends benefit.

The pen drive or flash memory packing was marked as 8GB capacity I bought it when I started to copy data on to it which was around 5.5GB suddenly, I got message on my laptop that drive is full.

I remove the drive from laptop and reinserted it but now I get another message USB device not recognized try on other PC get same message try to reformat it which also refused.

After a pain full Googling I found on some forum that a bad or corrupted flash memory drive can be repaired found some tools but no luck, Finally I found a tool which formatted my USB flash drive and indicated that the correct capacity is 4GB drive start working, for whole benefit I uploaded tool to 4shared

Home page: RMPrepUSB

How to repair bad or corrupted flash memory drive this was explained in software help on page 11, with this method using I repair my two flash memory drive.

You can easily identified the fake drive before purchasing see attach image original always mark with serial and fake have no serial
47_1292994168_thumb.jpg

93_1292994219_thumb.jpg

Before removing pen drive always used safe removal also set the hardware properties as shown in attach image
18_1292994308.jpg

Further never run any application from flash drive (if your USB drive is not a U3 smart) as system DLL hook up with drive and safe removal will not work, if you removed drive by force it will corrupt the flash memory unless you restart the PC I personally used pen drive only for back up or data transfer

Regards
Fragrance
 
Last edited by a moderator:

hi.....
i have gone through ur article..
its very useful...i m also having one pen-drive of Transcend 2GB but its not working....
can your tool fix it???
and can u explain why some pen-drives stops working even during short period of around 6months or smaller....??
thanks for posting such useful artical....
 

jigisha said:
hi.....
i have gone through ur article..
its very useful...i m also having one pen-drive of Transcend 2GB but its not working....
can your tool fix it???
and can u explain why some pen-drives stops working even during short period of around 6months or smaller....??
thanks for posting such useful artical....
Click to expand...

Hi
I am the author of RMPrepUSB and I would ask you not to make your own downloads or redistribute copies of it please. The home website for RMPrepUSB is sites.google.com/site/rmprepusb/ and you can download the latest version or latest Beta from there. It also has lots of articles which may interest you.

re. Fake USB drives - see sites.google.com/site/rmprepusb/tutorials/-fake-usb-flash-memory-drives which has lots of info.

If your USB drive is a fake one, then the memory inside it is probably of poor quality - I would not use the flash drive for anything except experiments - do not rely on it!

If the Windows 'Safely Remove Hardware' refuses to dismount your USB drive, try using Eject by right-clicking in Windows Explorer on the drive icon instead.

---------- Post added at 12:23 ---------- Previous post was at 12:07 ----------
jigisha said:
hi.....
and can u explain why some pen-drives stops working even during short period of around 6months or smaller....??
Click to expand...

There are two reasons:
1. You have a fake USB drive and the memory is unreliable - or it is only 2GB and not say 8GB and when you fill it up past 2GB it overwrites the drives cluster map and directories!
2. You do not ALWAYS use 'Safely Remove hardware' or 'Eject' the USB drive before you remove it from a USB port.

re. #2 - Windows loads the FAT cluster map into memory when it first sees a FAT16 or FAT32 Flash drive (which is why Windows does not let you have FAT32 partitions larger than 32GB as the cluster map would fill a lot of Windows memory). When you write a file to the USB drive, Windows may write the file data but not update the cluster map (which is cached in Windows memory) for several seconds. If you remove the USB pen without using 'safely remove hardware' system tray icon or 'Eject drive' and then pull out the USB drive, the directory/cluster map will not be updated and you will be left with a corrupt USB drive. Some USB pens (e.g. Netac) use Ultra-Stable Technology to avoid this problem - if you use one of these pens then all that will happen is that the last file you changed/wrote will be lost, but at least the whole filesystem is not corrupt. I have tested these Netac pens and they are MUCH more tolerant than others - however they are not the fastest of pens and also not the cheapest! However, if you need a Flash pen to transfer files between computers on a regular basis and you always seem to corrupt your pen drive every few months, I would recommend you buy one.
 
Last edited:

I have bought a fake usb flash drive a few years ago, it was supposed to be 8GB (and was reported as 8GB in windows) but the actual memory chips were about 1GB i think.
The only way i have found to check the flash drive is to write files that almost fill the capacity of the drive (you can use big movie files)
and then compare the CRC of the original files with the CRC of the files on the flash, if these are the same then your drive is really what it says.

Alex
 

steve6375 said:
Hi
I am the author of RMPrepUSB and I would ask you not to make your own downloads or redistribute copies of it please. The home website for RMPrepUSB is sites.google.com/site/rmprepusb/ and you can download the latest version or latest Beta from there. It also has lots of articles which may interest you.

re. Fake USB drives - see sites.google.com/site/rmprepusb/tutorials/-fake-usb-flash-memory-drives which has lots of info.

If your USB drive is a fake one, then the memory inside it is probably of poor quality - I would not use the flash drive for anything except experiments - do not rely on it!

If the Windows 'Safely Remove Hardware' refuses to dismount your USB drive, try using Eject by right-clicking in Windows Explorer on the drive icon instead.

---------- Post added at 12:23 ---------- Previous post was at 12:07 ----------



There are two reasons:
1. You have a fake USB drive and the memory is unreliable - or it is only 2GB and not say 8GB and when you fill it up past 2GB it overwrites the drives cluster map and directories!
2. You do not ALWAYS use 'Safely Remove hardware' or 'Eject' the USB drive before you remove it from a USB port.

re. #2 - Windows loads the FAT cluster map into memory when it first sees a FAT16 or FAT32 Flash drive (which is why Windows does not let you have FAT32 partitions larger than 32GB as the cluster map would fill a lot of Windows memory). When you write a file to the USB drive, Windows may write the file data but not update the cluster map (which is cached in Windows memory) for several seconds. If you remove the USB pen without using 'safely remove hardware' system tray icon or 'Eject drive' and then pull out the USB drive, the directory/cluster map will not be updated and you will be left with a corrupt USB drive. Some USB pens (e.g. Netac) use Ultra-Stable Technology to avoid this problem - if you use one of these pens then all that will happen is that the last file you changed/wrote will be lost, but at least the whole filesystem is not corrupt. I have tested these Netac pens and they are MUCH more tolerant than others - however they are not the fastest of pens and also not the cheapest! However, if you need a Flash pen to transfer files between computers on a regular basis and you always seem to corrupt your pen drive every few months, I would recommend you buy one.
Click to expand...

alexan_e said:
I have bought a fake usb flash drive a few years ago, it was supposed to be 8GB (and was reported as 8GB in windows) but the actual memory chips were about 1GB i think.
The only way i have found to check the flash drive is to write files that almost fill the capacity of the drive (you can use big movie files)
and then compare the CRC of the original files with the CRC of the files on the flash, if these are the same then your drive is really what it says.

Alex
Click to expand...
For a quick test you can use the RMPrepUSb quick test button - takes only a few minutes but just tests the size. It reports the actual size of memory afterwards.
For a thorough test use H2TESTW which is very slow but tests every unused byte.
 

steve6375 said:
Hi
I am the author of RMPrepUSB and I would ask you not to make your own downloads or redistribute copies of it please. The home website for RMPrepUSB is sites.google.com/site/rmprepusb/ and you can download the latest version or latest Beta from there. It also has lots of articles which may interest you.

re. Fake USB drives - see sites.google.com/site/rmprepusb/tutorials/-fake-usb-flash-memory-drives which has lots of info.

If your USB drive is a fake one, then the memory inside it is probably of poor quality - I would not use the flash drive for anything except experiments - do not rely on it!

If the Windows 'Safely Remove Hardware' refuses to dismount your USB drive, try using Eject by right-clicking in Windows Explorer on the drive icon instead.

---------- Post added at 12:23 ---------- Previous post was at 12:07 ----------



There are two reasons:
1. You have a fake USB drive and the memory is unreliable - or it is only 2GB and not say 8GB and when you fill it up past 2GB it overwrites the drives cluster map and directories!
2. You do not ALWAYS use 'Safely Remove hardware' or 'Eject' the USB drive before you remove it from a USB port.

re. #2 - Windows loads the FAT cluster map into memory when it first sees a FAT16 or FAT32 Flash drive (which is why Windows does not let you have FAT32 partitions larger than 32GB as the cluster map would fill a lot of Windows memory). When you write a file to the USB drive, Windows may write the file data but not update the cluster map (which is cached in Windows memory) for several seconds. If you remove the USB pen without using 'safely remove hardware' system tray icon or 'Eject drive' and then pull out the USB drive, the directory/cluster map will not be updated and you will be left with a corrupt USB drive. Some USB pens (e.g. Netac) use Ultra-Stable Technology to avoid this problem - if you use one of these pens then all that will happen is that the last file you changed/wrote will be lost, but at least the whole filesystem is not corrupt. I have tested these Netac pens and they are MUCH more tolerant than others - however they are not the fastest of pens and also not the cheapest! However, if you need a Flash pen to transfer files between computers on a regular basis and you always seem to corrupt your pen drive every few months, I would recommend you buy one.
Click to expand...

welcome my friends here in our paradise a nice place for electronic and software lover and thanks for more info i fixed my two USB pen drive with your tool

regards
Fragrance
 

jigisha said:
i m also having one pen-drive of Transcend 2GB but its not working....can your tool fix it??? and can u explain why some pen-drives stops working even during short period of around 6months or smaller....?? thanks for posting such useful artical....
Click to expand...
Fake are amost look alikes available from chineese manufacturers at a fraction of the Original cost thus attract buyers. If your new thumbdrive is not working, and you are sure that its a Brandnew opened from a sealed pack and not tampered, there are 90% chances you can get it working. I have dealt with 3-4 such drives (Trascend USA fakes) which were opened by me and found the soldering was not of good quality and was done with RoHs. You need to just re-solder all the visible points with a fine tip soldering iron with a good flux cored soldering lead. A cylindrical crystal will be found inside which without good bonding to the main chip, will not detect the device. I have got all my non working fakedrives working. I have Two 2Gbs, of Transcend, Two 4Gbs of Sandisk, and One 8Gb of Transcend out of which only two are genuine.
Cheers and good luck
 

hey....
thank you....
i will try to work on that......
may be i can recover my pendrive too...
 

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