I am getting the error message below now that I have upgraded. I see that others have had this problem but the solution has not been posted. Please advise.

"Warning: filemtime() [function.filemtime]: stat failed for xxx/xxx/joomla/media/com_easydiscuss/config.php in xxx/xxx/joomla/media/foundry/3.1/joomla/configuration.php on line 76"