Notebook cannot see an external drive: what checks should you consider before deeper diagnostics?

Introduction / Context:
When a notebook fails to recognize an external drive (USB, Thunderbolt, or eSATA), the fastest resolution often comes from a structured basic checklist. Many incidents are caused by connection, power, or driver issues rather than hardware failure.

Given Data / Assumptions:

• External storage enclosure or portable drive is being connected.
• Operating system normally supports plug-and-play storage.
• No explicit error message is provided yet.

Concept / Approach:
Always begin with fundamentals: physical connections, power state, and required software. Some enclosures require external power or a Y-cable for adequate current. Others need a vendor driver or encryption utility to expose volumes. Hot-plugging order can matter for certain legacy interfaces or older operating systems; replugging after boot sometimes triggers enumeration properly.

Step-by-Step Solution:

Verification / Alternative check:
Test the drive on a second computer. If it is recognized there, the issue may be OS drivers, security policies, or insufficient power on the original notebook port.

Why Other Options Are Wrong:
Each individual option addresses a real and common cause; since all are relevant, the combined choice that includes all of them is correct.

Common Pitfalls:
Using unpowered hubs for 2.5 inch spinning drives, overlooking disk initialization, and ignoring encrypted volumes that require software to mount.

Final Answer:
All of the above