Support topic: http://www.phpbb.com/community/viewtopic.php?f=46&t=2091805
When any user wants to attach a file with name like ''Mark's file'' or other using of combination of signs ''abc's file'', the final attachment's name showed in forum is only '' 's file'', the letters in front apostrophe are ignored.
I tested on my board with a filename containing single and double quotes:
test ' yy " xx.txt
Seems like all text before the last single or double quote is killed off.