Is there a way to scan a pdf to ensure it doesn’t contain anything that could be a virus?

The answers to Can a PDF file contain a virus? show that clearly it can!
Sometimes we can be quite sure a certain pdf should not need to do anything sophisticated – for example a book in pdf form – so we wouldn’t expect them to contain emb… Continue reading Is there a way to scan a pdf to ensure it doesn’t contain anything that could be a virus?

How can you tell if an email is really from the address it claims it’s from? [duplicate]

I am creating a basic website contact form. It requires entering a ‘from’ email address. I entered a dummy email address, which I do not control, yet the email is still sent, and, to the recipient, it looks as though the email came from an… Continue reading How can you tell if an email is really from the address it claims it’s from? [duplicate]

How to best prevent data recovery on a disk drive without physically destroying it? [duplicate]

The recommended way of ensuring that data on a hard disk cannot be recovered is to destroy it physically, for example using a hammer, drill or even thermite.
Question
When physical disk destruction is not an available option, what is the n… Continue reading How to best prevent data recovery on a disk drive without physically destroying it? [duplicate]

How to ensure that information deleted from external hard drive cannot be recovered after being sold? [duplicate]

I’ve finished migrating data from several drives on to one newer disk. The older drives were a mix of old mechanical drives, thumb (flash) drives, and SSDs.
Now I will dispose of the worthless drives and sell the rest. In order to sell the… Continue reading How to ensure that information deleted from external hard drive cannot be recovered after being sold? [duplicate]