My Book Live Duo - replacing a HD

I have a My Book Live Duo 8TB Personal Cloud Storage NAS.

One HDD failed. It’s a 4TB HGST 0f14697.

This is the first NAS I owned so I have some basic questions:

  1. Can I replace the faulty HDD with any 4TB drive, or does it has to be the exact model?

  2. If both HDDs must be identical, can I insert two HDDs from other manufacturer / other sizes (like two 8TB for example)?

  3. Any recommendations?

I’ll be grateful for any answer/tip/advice! Thank you!

Normally, WD recommends that you use the same line of drives if is not the same, something that is almost the same.

See if the following link helps:

Thank you!

In the manual it says: “Important: Only WD large capacity hard drive assemblies can be inserted into the My Book Live Duo drive enclosure. Visit and search the Knowledge Base Answer 8644 for detailed instructions on obtaining a replacement drive for this product. Use only WD hard drive assemblies or your warranty will be voided.”

But there is no list or “detailed instructions on obtaining a replacement drive for this product.” under answer 8644…

So from what I understand, any large size WD/HGST HDD should be fine, even if it’s a different size. Is that right?

Before I buy a replacement, I want to be sure: can I replace one 4TB HGST 0f14697 with a 4TB WD WD40EZRX?

Will the NAS work with one 4TB HGST 0f14697 and one 4TB WD WD40EZRX?