Basically, the error is still being thrown. You could use a bit of jQuery to cover it up (just add it alongside the rest - it's in script element tags, so it won't be seen like ordinary html - I included it after the last </div> I'm using on my pet's profiles before even closing the message variable). Of course, this'll only work if you have jQuery as part of your theme's template (Bootstrap theme definitely does):
Code:
<script>$(\"h2:contains('An error has occurred.')\").remove();</script>
The code literally removes any h2 element that contains the words "An error has occurred." - gotta love jQuery. The quotes are backslashed as they need to be going into the $message variable. Can't have quotes inside other quotes inside other quotes without the system getting confused, so, backslashes. Yay. -_- (It originally took me a while to figure out.)
And, incidentally, you can change your error message text site-wide from lang/lang_global.php -- so if you happen to change it there, be sure to update the snippet I just provided to reflect that.
(** And yeah, Abronsyth, I forgot to include a pet image -- my pet images are rendered with some custom code, so I took my bit out but couldn't remember the original -- thanks for providing that snippet of code!!)