SanDisk Ultra 128GB

Hello, SanDisk Forums!

I’ve come across an error where I must format my SanDisk Ultra before storing a file to it.

It’s a 128GB, but the capacity according to Windows, it’s a 32GB.

This is wrong, and I’m not sure if it’s supposed to be FAT32, exFAT, or NTFS, as well as the Allocation unit size.

Please help me!


If it’s new return it to the seller.  If it’s used return it to the seller. If it’s counterfeit your screwed.

New drives that size are formated exFAT.  Fat32 only supports drives up to 32 GB.

1 Like

Okay, thank you for this. I was so scared, but if returning it to the seller is the solution, I’m sure I can.

Hi there,

I have a Cruzer Glide 128 GB, ExFat formatted, which I have been using both on Windows XP and OS X 10.10.5 for quite some time without any probems.

All of a sudden OS X will not mount the unit, so I cannot access my info, and neither will Windows XP.

OS X\ Disk Utility, will not fix nor reformat it, the error being " Unable to write to the last block of the device ".

Windows XP’s\ Computer Management\ Disk Management, detects the USB as “E: Removable 119 GB Online,  Healthy”, reformats the unit to 100%, and at the end of the process displays the message " The unit was not successfully formatted"

Sorry to be posting this here, but I’m new in this forum and could NOT figure out how to start a new thread.

All help will with this problem will be GREATLY appreciated !



I assume you are reformating it as exFAT, right?  Does OSx support exFAT?  Does Windows XP?  FAT32 won’t work on the drive, it’s too big.

See if you can reformat it on a newer Windows system.

You probably need a new card reader:

This is for USB drives:


I had the same problem and the fix was easy.

1.  On the windows icon at the bottom left-hand corner, right click.

2.  Select Computer management option from menu.

3.  Under the Storage menu select Disk Management.

4.  On the right there will be a list of drives under Volume.

5.  Select the SanDisk drive and you will see there that it will have two paritions.

6.  Before proceeding to Step 7, make sure that all information on drive has been backup or saved on another drive

7.  Right click on the partitions and delete them. It will likely say 119.25 GB unallocated after you delete them.

8.  Now you can format the entire drive as one. Right click and select New Simple Volucme…

9.  A wizard menu will appear follow the instructions. I simply select next to everything and finish.

10.  When done the drive will pop up, close it.  And in the Computer Management you will find the assigned drive.

11.  It shoud say "Healthy (Primary Partition). It’s ready to be used.

I hope this helps…


rayT’s solution worked for me. Thanks! 

Hello rayT! Do you know any way I can do that SAVING the things inside? I cannot acces to the info inside because my computer never finshes reading the SanDisk unit…

Thanks and sory for re-asking here… I’m not sure it this was for another thread or right in here…

thanks for the help. It works for me.
But I have to mention the following:

  1. My SD Card was used on my Samsung A21s phone.
  2. After applying the method you describe, I’ve inserted the Sd Card back onto the phone, and the phone performed its own NTFS format. KEEP THAT IN MIND!
  3. Only after that I’ve recopied back all the data, as they have been before (with no changes to the directories) onto the SD card.

    Many thanks and keep up the good work!