Hi, If you suspect it has virus you could just scan it with an Antivirus Software. If you are using Windows. You could try right clicking the flash drive and click properties and go to tools in the menu tab, and below error checking, Click on check. Windows then will scan the drive for errors. Windows will then repair the drive if it detects any errors in the drive. If you could not right click it you could install a third party drive repair application online. If you are using Linux or Mac, I can't help you, I never used these operating systems before.