Symptoms
- No notification or sound when plugging the drive in
- Drive doesn't appear in File Explorer or Disk Management
- Drive works in one USB port but not another
- Computer says 'USB device not recognized'
Likely causes
- CommonFaulty or dirty USB portLint and debris in a port can prevent a solid connection.
- CommonDrive's USB connector is damaged or bentRepeated plugging can loosen or damage the connector pins.
- PossibleCorrupted or outdated USB driversA driver conflict can stop new devices from being recognized.
- PossibleDrive's controller chip has failedThis makes the drive undetectable everywhere, even with a good port.
- Less commonDrive is a counterfeit reporting a fake capacityFake drives can fail unpredictably or refuse to mount at all.
What to do
- Try the drive in a different USB port, and try a USB 2.0 port if only 3.0 ports are available.
- Inspect the port and the drive's connector for visible dust, bent pins, or damage.
- Test the flash drive on a second computer to isolate whether it's the drive or the PC.
- Open Device Manager and look for the drive listed with a warning icon, then update or reinstall its driver.
- Try Disk Management to see if the drive appears there without a letter, and assign one if so.
- If it's invisible everywhere and the connector looks fine, the drive's internal controller has likely failed.
Tools and parts
- Second computer to test on
When to call a pro
If the drive is completely undetectable and holds files you need, a data recovery specialist can sometimes read the memory chip directly.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.