We can check it in Windows Disk Management. The issue also results to a problem: we cannot change drive letter to D drive. Sometimes, the DVD drive is occupying the drive after a reboot or reconfiguration. The CD or DVD drive takes up the drive letter. There are three most possible reasons account for the D drive suddenly missing problem in general. Why can’t we see D Drive in Windows 10/11? When and why would that happen? How could we get the lost partition back exactly? Let’s keep reading. It will be quite annoying if we lost those files. Generally, we install operating system on C drive and install some third-party as well as our crucial personal data on D drive or E drive. As a matter of fact, people would find their local disk D missing in Windows 7 as well, E drive missing sometimes. It is a helpful post on how to find the lost D drive in Windows 10 after installing. Does anyone know what can be the problem of my computer? I need all data back at the same time. Worse is, I saved all data on that drive. It seems like completely missing from my computer. 'I have installed Windows 10 on my Alienware a few weeks ago and I cannot see my D drive now.