2TB hard drives showing up as only 1TB

I have 3 Western Digital external hard drives that are 2TB, and all over a period of a month are blank and show up in Disk Manager as only 1TB.  I am thinking the onboard controller on these fail.  Anybody else struck this, and … got a fix?  SMART data is fine … ??

Welcome to the Community.

Does this happen with any computer you have tried?

Hi Trancer.  Thanks for the response.  Yes.  Shows up on any computer.  I have also tried many adapters as well.  Just comes up as 1TB Raw and wanting to be formatted, which is understandable seeing as the drive size/partition info has changed.


Have you tried a low-level format (Write zeros)? This will completely clean the drive’s sectors in case there’s something wrong with the RAW partition.

Additional information is available in the following link:


Tried that for the day.  Windows re-registered the disk, through disk manager, but it still is showing up as only 931gb (1TB).  I’m thinking it’s a lost cause. :slight_smile:

WD20EARX - 32PASBO is my green WD 2T this is problem i use win10 its intrenal disk

i added a 2TB disk and it shows only 1tb. I check in disk management and its 1tb there also. It does not show second partion or unallocated space, and i do not have “extend partition” option.

I check in WD diagnostic tool and it also says 1tb , HD Tune also says 1tb , i try acronis disk director program and also see only 1tb . serial number WCAZAE421200 WD green

What’s going on here and how to see all 2TB ?

If you’re experiencing issues with three Western Digital external hard drives all showing up as 1TB in Disk Manager when they should be 2TB, it’s possible that there may be a problem with the onboard controller or the drive itself. Here are some steps you can take to troubleshoot and potentially fix the issue:

  1. Check for Data Loss: Before proceeding with any troubleshooting, make sure you have backups of the data on these drives. If the drives are malfunctioning, you don’t want to risk losing your data.

  2. Update Firmware/Drivers: Check if Western Digital has any firmware updates or driver updates available for your specific external hard drive model. Sometimes, a firmware update can resolve issues related to drive recognition.

  3. Test on Another Computer: Connect the external hard drives to a different computer to see if they are recognized as 2TB there. This can help determine if the issue is with your computer’s USB ports or drivers.

  4. Use a Different USB Cable: A faulty USB cable can sometimes cause problems with drive recognition. Try using a different USB cable to connect the external hard drives.

  5. Use a Different Port: Plug the drives into different USB ports on your computer. Sometimes, certain USB ports may have issues.

  6. Check for Disk Management Errors:

    • Right-click on “This PC” (or “My Computer”) and select “Manage.”
    • In the Computer Management window, click on “Disk Management” under “Storage.”
    • Check if the drives are showing up correctly there. If not, they may need to be reinitialized or reformatted.
    • Be cautious when reformatting, as this will erase all data on the drives.
  7. Data Recovery: If you can’t get the drives to show up as 2TB and you have data you need to recover, consider using data recovery software to retrieve your files before attempting any further troubleshooting.

  8. Contact Western Digital Support: If none of the above steps resolve the issue, it’s possible that there is a hardware problem with the drives’ controllers or the drives themselves. Contact Western Digital’s customer support for further assistance, especially if the drives are still under warranty.

  9. Professional Data Recovery: If the data on the drives is critical and you cannot recover it yourself, you may need to consider professional data recovery services. These services can often retrieve data even from malfunctioning drives.

Remember that if the SMART data is fine, it doesn’t necessarily rule out hardware issues. SMART data mainly provides information about the drive’s health but may not detect all issues, especially those related to the external enclosure or controller. Always prioritize data backup and proceed with caution when troubleshooting to avoid data loss.