Here it is. I have just changed the category name. I get no error message, nothing.
"CATEGORIES","SUMMARY","LOCATION","DESCRIPTION","CONTACT","X-EXTRAINFO","DTSTART","DTEND","TIMEZONE","RRULE"
"Knowledge plus","Football Match","Football Stadium","This event is just for fun","Contact Name","Whatever extra-info","20100915T150000","20100915T191500","Europe/London","FREQ=DAILY;COUNT=10;INTERVAL=3"