There are certain reasons & some very easy fixes:
- The USB is not yet formatted.
- The system you are using has its port as FAT & not NTFS.
- The USB has been affected either by Virus or Trojan, etc, i.e., it has become malicious.
- The USB is corrupted.
Solutions--> (point wise)
- Please format the USB either via right clicking & formatting from the options, or through cmd (command lines). Do give a name once its formatted.
- The Current market USB are all NTFS formatted & not FAT, & since the OS might be FAT Port accessible, you would have to follow the same point 1 process.
- If this is the case, then please run a scan through MBAM or GMER, which will check for any Trojans & any Root-Kit problems for the same.
- For this point, there is no solution, but to get it replaced if within period, or buy a new one.
Hope, this helps.
Please do let me know, if this helped or not!