Question Error "Cannot save message"

I am using J 3.4.8 and Kunena 4.0.9, along with CB 2.0.13. Occasionally when members try to post something in the forum - when they hit "Submit" the entire post disappears and they get an error message that says "Cannot save message: Message body is empty!"

Using a technique suggested on this forum from about 3 years ago, I turned on Preview while typing in a message. I played around with one of the messages that one member could not post. As soon as I entered any word starting with or and surrounded by single quotes (i.e., 'or') the words in the post disappear from the preview. When I removed that part of the post, the words would reappear in the preview. I tried other combinations and the 'or' was the only one that caused problems. Any ideas why or how to track down the offending code would be greatly appreciated (I'm guessing there's something in the code somewhere that causes this problem)? It does not seem to be a problem here in this forum. We had not experienced this problem prior to upgrading Kenuna and CB.

Turns out it is a security setting by the hosting company. This is what they said

The combination of ('or) is known to be used in hack attempts in the past for compromising Joomla application. It is basically used to escape some code and allow the attacker to hack the website.

jHackGuard plugin that you also have installed on your Joomla applications ... escapes such combinations by default.

Ok, then you need to turn off that option setting from your hoster