This is a strange one, and I can only assume it is a bug. I am not a programmer in PHP & I am relatively new to Xenforo, so I apoligize if this is not a bug - but then what is it? So I get the error when I post a particular word. The error occurs when both replying to a post and when in "conversation" with someone (i.e. private message in Xenforo) and including a particular word Here is a screen shot of the Xenforo error pop-up: so the word is Zyrtec just to be clear, the error occurs only with this word, no other word triggers this error. The error is triggered if the post only contains 1 word, being "Zyrtec" -or- if I write 100 words and 1 of the words is "Zyrtec". What on earth is going on? A bug? NB - I do not have this word in the "Censoring" functionality of Xenforo.