I have no idea how to formulate a fitting thread title, so please bear with me.
My dad had some super confidential files on his USB stick and he asked me to encrypt them, so nobody else but him could access them.
So I put the USB into my PC, created an encrypted storage with TrueCrypt and stored the confidential files in that storage. I have not copied the files to my PC, nor was the truecrypt storage ever on my HDD. Everything happened on that USB stick.
My dad now wants me to shred the HDD... I've got no real clue if somebody could recover those files from the HDD, even though it has never been on it.
Is simply inserting a USB and moving files around on the USB enough to leave traces on the PC?
Before somebody asks wtf was in those files... don't even bother, I've got no clue myself. Just some text files... so no picture preview or anything that could have been triggered.
For now I have told him that shredding my HDD is no option. I would have to buy an external to save my stuff before even considering something like this... But my dad is pretty serious about this.
To clear things up a bit: My dad has his own company. They are quite successful and 'big', but he got no IT stuff or anything. Yet they have to deal with confidential things and they have to hide things from their competitors. He is paranoid about getting hacked after he noticed some strange log ins into his email account...