After converting to UTF-8 , Big problem

[محروم.كوم]

Hey,
I convert my forum to utf-8 , from 2 weeks , afterthat i see very low replies and new threads and don't know the issue , today i know that when member submit new reply or thread , this message comes with blank page

Code:
Warning: Invalid argument supplied for foreach() in [path]/includes/functions_editor.php on line 710
I know that problem with bbcode , when inhibiting it from PMs , it solves
but still found in replies and threads

Please i need a help
Thanks __DEFINE_LIKE_SHARE__