I'm getting the same error:
Warning: array_search() [function.array-search]: Wrong datatype for second argument in /home/content/--/-------/html/wp-content/plugins/all-in-one-event-calendar/all-in-one-event-calendar.php on line 160
Fatal error: Cannot use object of type stdClass as array in /home/content/--/-------/html/wp-content/plugins/all-in-one-event-calendar/all-in-one-event-calendar.php on line 160
This happened last month after I updated another plugin (possibly the all-in-one).
Anyways, I had to get someone to reinstall the plugin. Unfortunately in the process I lost the date, time, organiser and cost details. A total disaster. And it cost a bit to fix.
Now it has happened agin. This plugin seems to have bugs/compatibility issues.
Maybe the author can suggest a fix that won't cause me to loose the data again.