Clean/custom error pages and error templates

I use an OnError function in my application.cfc’s to show only a cleaned up error message across my application, until today I thought that’s all I needed, My site was under extreme load, some timeout errors occur and users started to show me their error screens, with a error dump labeled “Lucee #### Error (expression)” after my custom error output.

from another post on here, and from what I found in the file, I am assuming that it was coming from [webroot]WEB-INF/lucee/context/templates/error/error.cfm

I have just commented out this file, is that effective? what is the best practice here? and what causes that error template to show, after the error has been captured by the OnError function; when it typically does not?

You can change the error files used in the Lucee Admin, it is best not to touch the files in the Lucee context folder as they might get changed during an update.