Check this first
The short answer
Compare a direct connection using a cable rated for the required data or video function, then another port with the same device. An error code describes a reported state, not the failed part. For an SSD absent from File Explorer, inspect Disk Management: a healthy data volume without a drive letter needs different handling from RAW or uninitialized storage.
- Finish storage transfers and use safe removal where available before unplugging.
- Compare a direct connection with the supplied compatible cable and another port.
- Record warnings and codes; for an SSD, inspect whether Disk Management detects it.
Choose your next check
Start with the row that matches your situation. Change one setting at a time so you can tell what helped.
| What you see | What to compare | Go to |
|---|---|---|
| Charging works but data transfer does not | Compare a direct connection with a data-capable cable and another port. | Step 1 |
| USB device not recognized or a yellow warning | Record Device status; do not identify the cause from the code alone. | Step 2 |
| The SSD is missing from File Explorer | Inspect its capacity, status and drive letter in Disk Management. | Step 3 |
| A healthy SSD volume has no drive letter | Confirm it is the external data volume, not a system or app volume. | Step 3 |
| The SSD is RAW, unallocated or uninitialized | First decide whether existing data is needed or it is definitely unused. | Step 3 |
| Only video from a USB-C dock or monitor fails | Check video support on the exact PC port, dock and cable. | Step 4 |
| USB4 or Thunderbolt functionality is limited | Compare the device’s requirements with the entire connection path. | Step 4 |
Check in this order
Continue this issue
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Step 1: Compare the direct connection, cable and port
- Finish any copy operation on an external SSD or flash drive. Where available, use the taskbar’s Safely Remove Hardware and Eject Media action and wait for safe removal before unplugging.
- Bypass the hub or dock. Connect directly with the supplied cable or one explicitly rated for the required data/video feature. Record the connection notification, app or File Explorer appearance and any video.
- Change one thing at a time: the same device and cable on another port, then another compatible cable on the same port, then another available PC. Successful charging does not prove data or video capability.
- Expected result or what you learned
- Direct-only success points toward the intermediate hub/dock or its power. Cable-only improvement prioritizes that cable. Success on another PC directs attention to the original PC’s port or configuration.
- If something is wrong or unclear
- For a warning use Step 2. For recognized storage absent from File Explorer use Step 3. For video-only failure use Step 4.
- How to undo changes
- Follow the device’s removal instructions and safely eject storage before restoring wiring. Keep a working combination rather than recreating a failing connection unnecessarily.
Step 2: Read Device Manager status and codes
- Right-click Start → Device Manager. After safely stopping storage use, compare the device list before and after reconnecting. Look for new names or warnings under Universal Serial Bus controllers, Disk drives and Other devices.
- Open the newly identified device’s Properties → General → Device status and record the exact message and code. Do not guess and uninstall another device or the PC’s USB controller.
- Code 28 means the required drivers are not installed: find the manufacturer’s Windows 11 package for the exact PC/device model. Code 43 means Windows stopped a device after a reported problem; combine it with Step 1’s cable, port and other-PC results.
- Expected result or what you learned
- Code 28 points to missing drivers. Code 43 can involve the device or driver and cannot by itself prove a faulty cable.
- If something is wrong or unclear
- With no code, an SSD listed under Disk drives still belongs in Step 3. For video-only failure use Step 4. If nothing appears, send Step 1’s comparisons to the manufacturer.
- How to undo changes
- Viewing status changes nothing. If a supported driver installation introduces another problem, record the installed version and follow the manufacturer’s rollback guidance.
Step 3: Use Disk Management status to choose the storage check
- Right-click Start → Disk Management. Identify the external SSD by capacity, product information and changes after safe reconnection. Do not select the internal Windows disk or another volume by guesswork.
- Record whether it is present, Online or Offline, Healthy, Unallocated or RAW, and whether a letter such as E: is assigned. Reading these fields does not change the data.
- If previous files are needed, close initialization or formatting prompts without proceeding. Treat a definitely unused new disk separately and choose the matching result below.
What the result means and what to do next
| Situation | What it tells you | Next action |
|---|---|---|
| The expected capacity is absent | Windows has not detected the storage portion. | Compare direct connection, cable and another available PC. If only another PC sees it, ask about the original PC’s port and driver. |
| Online, Healthy, NTFS/exFAT data volume, but no letter | The recognized volume may lack a File Explorer access letter. | Only after confirming an external data volume, use Change Drive Letter and Paths → Add → an unused letter → OK. This requires appropriate administrative permission. Do not modify C:, Windows or app volumes. |
| Online, Healthy and a letter is assigned | Connection and volume recognition have progressed. | Find the same letter under This PC and check existing files. For access denied or another failure, record the message; do not choose Format. |
| Offline or 0 B | Power, connection or disk state may be involved; the label alone cannot decide. | Compare power and connections. If data matters, ask the manufacturer rather than repeatedly bringing it online or running repairs without knowing why. |
| RAW, uninitialized or unallocated, with existing data needed | Windows may not be able to read its filesystem or layout; this does not mean unused. | Do not initialize, create a volume or format. If safe, make one comparison with another cable or PC; if unreadable, seek data-recovery advice. |
| Definitely new, unused and without needed data | The disk may need initial preparation. | Confirm capacity and disk number. For a disk supporting initialization, right-click Disk n → Initialize Disk and confirm the intended disk and partition style. Then right-click its Unallocated area → New Simple Volume and follow size, letter and filesystem choices. This writes a new layout and formats storage; never proceed if any previous data is needed. Some USB drives do not use initialization. |
- Expected result or what you learned
- If assigning a letter to the confirmed healthy external data volume makes it appear under File Explorer → This PC and existing files open, that storage is usable for the test.
- If something is wrong or unclear
- Record any assignment or access error. If a previously used SSD is RAW or uninitialized, prioritize data recovery instead of recreating its layout.
- How to undo changes
- Inspection alone needs no undo. A test letter can be removed through that same volume’s Change Drive Letter and Paths after closing files and apps that use it. Initialization and formatting have no simple undo.
Step 4: Check video, dock and USB4 feature support
- Record the PC and dock models. Check the specifications of the exact USB-C port in use for video output such as DisplayPort Alternate Mode and for required USB4/Thunderbolt support. Connector shape, data, charging and video capability are separate.
- For a blank monitor, compare direct PC-to-monitor connection with a video-rated cable against the dock path. Check the dock’s specified power supply if it needs one. Use Windows + P → Extend, then Settings → System → Display → Multiple displays → Detect.
- For limited USB4 or Thunderbolt functionality, compare device, cable, dock and PC port requirements individually. A driver cannot add a physical port capability that the PC lacks.
- Expected result or what you learned
- If direct video works but the dock does not, prioritize dock power, supported features and cable. If Windows detects display 2, inspect the monitor’s selected input as well.
- If something is wrong or unclear
- If a supported direct path is still undetected, provide models, a connection diagram and detection results to the manufacturer. Use the second-monitor guide for display-specific branches.
- How to undo changes
- Restore the previous Windows + P display mode and follow each device’s instructions when restoring cables or the dock.
When to ask for help
Provide PC, device, cable and dock models, direct/hub/other-port/other-PC results and error codes. For an SSD add Disk Management capacity, status and drive letter. When previous files matter, seek recovery advice before initialization or formatting.
FAQ
Does Code 43 prove the cable is broken?
No. Compare the same device using a compatible cable, another port and an available second PC. Record which combinations detect it; the code alone does not identify the failed part.
Why does USB-C charge but show no video?
Power delivery and video are different functions. Check that exact PC port, cable and dock for video support, then compare the direct path in Step 4.
What if another PC can read the external SSD?
Back up needed files there first. Compare the same cable on another port of the original PC, then record its port, driver and Disk Management state. Do not format a readable disk to investigate another PC.
Sources
English adaptation preserving the Japanese guide’s diagnostic branches, steps, outcomes, undo instructions and official sources. Official guidance was reviewed; these comparisons are not claims of testing every cable, dock or device. Confirm the exact model and required features. Ask the administrator before changing a managed PC.
Microsoft: USB-C connection and feature compatibilityMicrosoft: Device Manager error codesMicrosoft: external monitor connectionsMicrosoft Learn: assigning a drive letterMicrosoft Learn: initializing a new disk and protecting existing data