Antivirus system and method for removable media devices

A removable media device, which may be a USB attached device or other type of removable media device, includes a software program located on the device which upon startup or access, the software program scans one or more of electronic files stored on the removable media device and electronic files being transferred to or from the electronic media device and to or from a host computing system for the detection of viruses therein. The software program is further configured to block the transfer of detected virus-containing electronic files and to disallow the copy or writing of files to or from the removable media device to or from a host computing system that can not be scanned. The software program is further configured to block the encryption of files being written to a removable media device if such device contains hardware or software encryption if such files can not be scanned.