Flash videos play on some sites but not others; some sites just display a black box. Tried googling but no solution I found worked. So I created a new user account (with the same privileges) and all flash videos play on that account. Why would they all play on one account but play selectively on the other?
"So switch accounts..." - yeah but the work... THE WORK!!
Figured it out!
deleted all the subfolders / files in C:\Documents and Settings\[user name]\AppData\Roaming\Macromedia\Flash Player\macromedia.com\support\flashplayer\sys
and they work now -