How to Troubleshoot a Flash Drive That is No Longer Recognized by a PC
A flash drive, also known as a USB drive or a thumb drive, is an external storage device that plugs into the USB port of your computer. Sometimes, error messages will come up that indicate your computer failed to recognize the flash drive when you plugged it in. This is not an unusual problem and there are ways to fix it.
Pull out your flash drive. Wait for a few seconds and then plug it back in. Sometimes, a simple restart can troubleshoot the issue.
Navigate to the Microsoft Support web page. Click the green button labelled "Run now." Wait patiently as Microsoft tries to troubleshoot the issue.
Click "Start" menu and select "Run." Type without any quotes "devmgmt.msc" and press the "Enter" key. This will launch your Device Manager. Double-click to expand "Universal Serial Bus controllers." Look for an entry that has a red exclamation mark next to it. Right-click it and select "Update Driver software." A back-dated driver can cause issues with external storage devices. Go to the next and final troubleshooting step, if this doesn't solve the problem.
Format your flash drive. This will delete all your data from the flash drive and should only be used as the last option. Click "Start" and select "Computer." Right-click the flash drive under "Devices with Removable Storage" and select "Format." Choose NTFS format since it is compatible with most external storage devices. Follow the on-screen prompts to complete the format.