How i can get all disk space

I have 12 TB but in windows i have only 3TB, how I can use all 12 TB ?

Hello,

What RAID setup are you using?

What Windows version are you using? XP? Vista? 7? 8? 10?

This sounds similar to the problem I have. I have 4 drives installed in the EX4, but only the first one shows up as available, although it says it has the full amount of storage available. The setup was to be JBOD. Also looking to add external drives via USB.