Make your pendrive "virusproof"
Note: I dont have a english OS, so I did free translation.
I will post images, although it is hard to understand because of the language you should see how I did all the steps located.
I havent tried with a usb HDD because i dont have where to put all my data to format it, but if anyone wants to try, give some feedback
1st step:Format your pen drive as FAT32 (right click on your pen icon and click format)
2nd step: Now we are going to convert the pen drive to NTFS, open cmd.exe and type "convert e: /fs:ntfs" (without quotes), where "e:" is the pen drive letter attributed by windows
p.s: not "it" its "hit"
3rd step: Open mycomputer, then folder options and untick "use sharing assistant"
4th step: Make a new folder in your pen drive, and from now you will put your files in that folder
5th step: Now right click in your pendrive icon, click properties and go to the security tab
6th step: In permissions for all users only leave ticked the "read and execute", "list folder contents", and "read"
7th step: Repeat step 6 but instead of setting the security parameters to the pendrive do it only for the folder that you created inside it.(Now edit permissions again to all users but now give total control)
By doing this your flash drive will not allow to be written or executed and files at its root, where they host the malicious files on your pendrive, the folder that you created will have total control and without the existence of virus.