How to help people who may suffer from Paranoia? I am a very active member of the Information Security Stack Exchange site. Every now and then, I come across people who I believe may suffer from paranoia. They believe that &quot;someone&quot; is out to get them, and use techno-babble to make themselves sound legitimate. Here is an example post:

How to prevent attacker from viewing what's on my Android phone screen? Can someone give me advice or suggest apps to prevent this?
For example, if I write in notepad, and it's offline, they can read it. They know the time of my alarm. if I just set new random one they know. If I play some music, they know.

Another post by the same user:

they can read my screen, listen to my mic and even control my notification. both my rooted and unrooted phone. This happens when i just moved to new place im renting, it was bad neighborhood.

I'm not a psychiatrist, but I am very well-versed in security and I am 99.999999% certain that the things this person described are not real. I asked that person a few times who &quot;they&quot; were, and how he could know that someone was reading his messages. He claimed he didn't know who &quot;they&quot; were, but he was certain someone was watching him. As an example for &quot;proof&quot; he claimed that someone in his neighborhood was listening to the same song he was listening to a while ago.
The sad thing is, such users come to our site regularly and I am unsure how to best help them. What should I do when I come across a person who I suspect may suffer from paranoia?
What I've tried so far
So far, I have tried to tell those looking for help with their supposed hacker problems that they are likely not being attacked, and that it seems to me that they may be affected by paranoia. I tried to help them by adding links to credible organizations (like the Australian Better Health Channel), which was always countered by them claiming that they are not paranoid and that their problems are real.
I'm not sure if bluntly saying &quot;I think you may have a mental health problem&quot; is beneficial though, and if it may do more harm than good. For this reason, I am asking this question, how exactly I should act and how to best help people.
I'm not active on this board, so please forgive me if my answer is not up to community standards.

I am not a psychologist, but I have some experience with mental illness (maybe too much.)

True paranoia (or Paranoid Personality Disorder/PPD) is much more pronounced than thinking that people can spy on you through your mobile. Whether it's true or not isn't relevant, really. In this case, there is a kernel of truth to their fears, which becomes exacerbated.*


  According to the DSM-5, persons with Paranoid Personality Disorder will have trouble operating with others in the workplace, educational or social settings (American Psychiatric Association, 2013). It is noted that people with PPD are more frequently unemployed or working more menial jobs than the general population (Mueser, Mischel, Adams, Harvey, McClure, Look, Leung, &amp; Siever, 2013).They tend to be solitary, self sufficient, and secretive, and will have difficulty making or maintaining intimate relationships or close friendships. (American Psychiatric Association, 2013). Persons with PPD may experience a conflict, in that they want intimate relationships and friendships, but do not have a level of trust which is an essential element of such relationships. 


If many of the other criteria aren't met, it's probably not paranoia. On the other hand, if your interactions are limited, you may not know about other criteria, so this might be paranoia.


  How to help people who may suffer from Paranoia?


It's very difficult, even for therapists, because challenging their belief systems makes the person very defensive. They do not tend to have much self insight, which makes therapy challenging. Clearly you are not in a therapeutic relationship with the user; I would try to steer them in the right direction security-wise, and then (gently and respectfully) disengage.


  So far, I have tried to tell those looking for help with their supposed hacker problems that they are likely not being attacked, and that it seems to me that they may be affected by paranoia. 


I would definitely avoid this, as this is giving a diagnosis, which you should not do (I believe it's unethical) over a brief interaction on the internet. I'm not surprised they counter by claiming that they are not paranoid and that their problems are real. To someone who's paranoid, their problems are real.

In case my answer isn't well explained,


  I'm not sure if bluntly saying "I think you may have a mental health problem" is beneficial though, and if it may do more harm than good. For this reason, I am asking this question, how exactly I should act and how to best help people.


Unless you are in a close personal relationship with someone, I think it's not in their best interests to tell them they may suffer from a mental illness, whether they do or not. First, you do not know. Second, they will most likely be defensive if not offended as well.

My reaction would be to be kind and gentle with the person, avoid overt confrontation ("That's not possible...") and let people close to them tell them they need professional help.

*Laptop cameras have been hacked, and worse.  

**I know people who believe Pizzagate was real. Te truth doesn't matter if you like conspiracy theories.

References

American Psychiatric Association. (2013). Diagnostics and Statistics Manual of Mental Disorders (DSM-5) Washington. DC: American Psychiatric Publishing.