If you have a greyed out USB flash drive this article should be able to help you resolve the issue.
The most common reason is the USB flash drive has a different file system and you simply need to format the drive. For example, Ext3, Ext4 or HFS are file systems for Linux and Mac. By formatting the USB drive it could restore the drive and it’s no longer greyed out.
If this didn’t do the trick, then try the next suggestion ↓
It is possible the greyed out USB flash drive has a bad device driver. We can uninstall the drive and try re-installing the USB stick (reconnecting).
Do the following:
In the Search area type “Device Manager” and good chance Windows will auto-suggest before you are even done typing. Select Device Manager.
Alternatively you can click the Windows key along with “X” and from the list select Device Manager
Device Manager lists things alphabetically so scroll towards the button and expand the carrot > for Universal Serial Bus controllers.
In the sub-listing you will see the Mass Storage Device and then right click that device and select Uninstall device
Now the device drive has been removed, please reconnect the device and see if the greyed out USB flash drive is still greyed out.
If this didn’t do the trick we have one last suggestion for you before declaring the USB stick most likely dead ↓