Installing 4TB drive under windows 10 without UEFI

I have this new WD40EZRZ drive and I was wondering if it can be installed in a Windows 10 desktop, as drive D (not the boot drive) with the full 4TB capacity even though the computer does not support UEFI.

This is actually my second such drive. I was not able to get the first one to work right. It appeared as about 1.5TB. That’s less capacity than the 2TB drive I want to replace.

However, when I ran a quick scan from the WD Data LifeGuard utility it hung forever on one sector. So I returned it as defective and exchanged it for this one.

I installed this drive as Disk 1 and ran the same quick scan. It ran fine, so I think this drive is good. But before I initialize the disk I noticed that the Data LifeGuard utility sees the drive as 4TB but the windows 10 disk management utility sees it only as 1678.02 GB.

Here are some screen captures.

I have not initialized it yet although, when I do, I understand I need to initialize it with a GPT to get windows to recognize the full 4 TB.

I just wanted to check before going further, is there anything else I must do to get this initialized and formatted with the full 4TB capacity or, is it not possible, even as only a data drive, without UEFI?

Hi there,

I doubt this is a Windows problem as you are able to read and write to an 8TB drive.
Have you tried ‘Writing Zeroes’ to the drive using DLG?
Have you tried a different computer?
If none of the above makes a difference, I would suggest you contact WD Support for a replacement.

The 8TB drive is an external drive connected through USB, this 4TB drive is internal. Could that explain why the 8TB drive works and 4TB drive appears smaller than it should?

This is already the 2nd 4TB WD drive I’ve tried. I think the last one was defective because the quick scan would not complete. The quick scan on this drive completed in about 2 minutes. So, I don’t think the drive is defective.

I did not try another computer because my only other computer is a laptop.