I recently purchased an external hard drive to back up my music files before I put a new operating system on my computer. I wanted to know if I connect the external drive thru a USB port and leave it connected, thus excessible, if I were to contact a virus could the virus be spread to the external drive. Or if there I leave it connected and the system crashes for whatever reason and destroys all my files will the files on the external drive be destroyed too, simply because of the connection through the USb port. Lastly, if the answers to the previous are yes how can I have access to the external drive without risking the files on it. Any help in understanding this would be appreciated. Thanks