Recently on one of the websites I maintain, a strange message cropped up:
Here's how to fix it.
For a moment, I was three things
2) Pleasantly surprised
3) Somewhat disappointed
There are two ways to fix this message - which fixed our problem
1) Fix your HTML code - Many times what happens is that this content has either been migrated from a previous version of Joomla or migrated from somewhere else. Try opening the article in the back end and save the article. Many times, this will fix the problem. Your 2nd option is to actually switch to the HTML code of the article, find the email address and see if there are any mismatched html tags surrounding it, such as non-closed <span> tags, or other mismatched tags or HTML issues which will interfere with the cloaking functionality.
2) Disable the email cloaking - In case you want to disable this in Joomla, the only thing you need to do is Extensions Manager > Plug-In Manager > find the "Content - Email cloaking" plugin and disable it. Now that message will be gone, but so will your Spambot protection. For Spambot protection in Joomla, we do use a very good script, ZBBlock which works well on any PHP based website. We also use Joo Recaptcha, to protect registration and contact pages from Spambots. The two together have worked very very effectively to rid us of the huge amount of SPAM we used to receive. Now it's mostly legit requests which we get!