Given that I work in an audit/fraud/IT role I'm naturally a bit suspicious about incoming email scams, so having received this earlier my first thoughts weren't hugely charitable:
I noticed you've shared TrueCrypt on this page http://virtualdebris.co.uk/blog/0387F2E0, as you may be aware, development of TrueCrypt was discontinued back in 2014 and has subsequently not been maintained. A number of security flaws have been uncovered and as a result we are reaching out to people to highlight a list of alternatives.
Here's the list (along with further details about TrueCrypt no longer being maintained) - https://www.comparitech.com/blog/information-security/truecrypt-is-discoutinued-try-these-free-alternatives/, when you update your page it could be a useful resource to point your visitors to. Please let me know if you have any questions.
It's a pleasant surprise to discover that the article is balanced and worth checking out on the subject, rather than adfarm clickbait, and https://www.comparitech.com/ seems to be a decent tech journalism site in general.
The point about security flaws in TrueCrypt is small-c conservative, though. For another take you may want to read and/or download from Steve Gibson, who's always been a Marmite-like character but I'd be inclined to trust:
And if you're looking for an alternative, I've tried VeraCrypt on Windows and Linux and apart from window layout messing up a bit under the window manager settings I use in Xfce it's a decent continuation. For system drives I'd be inclined to use Bitlocker under Windows (although you can assume that details of any Microsoft accounts are wide open to law enforcement or anyone else that asks nicely, and that Windows itself is about as secure) or a dm-crypt based solution under Linux.
Also consider the relative sensitivity of the information most people are likely to be handling, and other ways it could be obtained. If someone wants your data enough they'll just use violence or a hardware keylogger. For securing stuff against the eventuality that drives or devices are stolen, the important things are to encrypt and to remember that strong encryption is worthless if a password isn't good enough and isn't only in your head or physically secure.