A drive missing from File Explorer is not automatically empty or dead. First find out whether Windows sees the hardware and how Disk Management describes it.
If the drive contains needed files: do not initialize, format, create a new volume, or accept an "erase" prompt.
1. Rule out the simple connection
- Disconnect the drive safely and restart the PC.
- Try another known-good cable and a direct USB port, not a hub.
- For desktop drives, verify the external power adapter.
- If possible, test the drive on a second PC without formatting it.
2. Open Disk Management
Right-click Start and select Disk Management. Identify the external drive by capacity and model; never rely only on "Disk 1" or "Disk 2."
3. Read the status before acting
- Healthy but no drive letter: adding an unused drive letter may make it appear in File Explorer.
- Offline: bringing the correct disk online may be enough.
- RAW: Windows cannot recognize the file system. Do not format if you need the files.
- Not initialized: initialize only when you know the disk is new and empty.
- Unallocated: do not create a new volume if the drive previously held files.
- Not present at all: focus on cable, power, enclosure, port, controller, or drive failure.
4. Know when to stop
Disconnect a drive that clicks, repeatedly spins up and down, disappears during reads, or becomes unusually hot. If the data is irreplaceable, avoid repeated scans and consider professional recovery.
Official references: Disk Management in Windows and Microsoft's initialization warning.