I have been receiving threatening emails from someone, and I don't want them to know my location for my safety's sake, but I need to send them a "Cease and Desist" notice. This person has great resources, both technical and financial, and I just wish to be left alone. What are my options?
Forgetting the reasons behind why you want to do this for the moment and focusing on the technical side of your question.
Your best bet would be the following:
- 1) Download Tails, a linux 'Live CD' which has a focus on privacy
- 2) Load it up on your laptop, connect to wifi at a public hotspot such as Starbucks or McDonalds (pay in cash if you intend to eat/drink anything)
- 3) Connect to the TOR network (it should be integrated into the Tails distro)
- 4) Pick one of these 'snoop proof email providers' and sign up for an account
- 5) Only ever access the accounts/send mail etc via the above steps
- 6) Shut down your computer, remove the Live CD and leave the internet hotspot. There should be no evidence of your email anywhere
Note: While your in the Tails environment, DO NOT do anything outside of your intended purpose (such as checking your real email/facebook etc), this could potentially be linked back to you if you do. Furthermore, DO NOT be tempted to check on your email account from home/work etc. Only ever do it from within the live CD, on the TOR network at an internet cafe of some description.
Technical stuff aside, listen to the other advice posted here and seek legal advice.
A "Cease and Desist" notice sent via email, untraceable or otherwise is not likely to be effective. Terry's comment suggesting you call the police is a much better option, but perhaps the best is to get a lawyer involved, and have the individual served with an actual, legally binding order of protection, or whatever similar instrument you may have locally available and jurisdictional approved.
Unfortunately, sending an untraceable email is relatively easy, particularly when compared to getting someone unsavory to leave you alone.
If you know this person, which I am assuming you do and their communication attempts are threatening your well being, you can and should contact the law enforcement before it is too late.
Short of that, to make tracing you harder if not totally impossible, download and setup "Tor Browser" (just Google the term). Set up a new email with your choice of the free webmail providers. Send your email and abandon the account. Although, for someone with abundant resources, this will be no deterrent and probably, not being able to trace you will make them even more angry and making the pursuit more "enjoyable" for the lack of a better term. And if you send an anonymous email, what good will this make for you, should the things go law enforcement way one day ?