When attempting to merge/subscribe the following error is received:
"Unable to read the calendar (try setting the 'relaxed parsing mode' in
the calendar administration options): Error at line 1: Expected [BEGIN],
read [<!DOCTYPE HTML PUBLIC ]"
We have set the relaxed parsing mode but it had no effect.
Error from Logs:
2007-11-15 12:40:22.050844500 Caused by: net.fortuna.ical4j.data.ParserException: Error at line 1: Expected [BEGIN], read [<!DOCTYPE HTML PUBLIC ]
2007-11-15 12:40:22.050878500 at net.fortuna.ical4j.data.CalendarParserImpl.assertToken(CalendarParserImpl.java:411)
2007-11-15 12:40:22.050897500 at net.fortuna.ical4j.data.CalendarParserImpl.assertToken(CalendarParserImpl.java:386)
2007-11-15 12:40:22.050920500 at net.fortuna.ical4j.data.CalendarParserImpl.parse(CalendarParserImpl.java:96)
2007-11-15 12:40:22.050942500 at net.fortuna.ical4j.data.CalendarBuilder.build(CalendarBuilder.java:165)
2007-11-15 12:40:22.050969500 at net.fortuna.ical4j.data.CalendarBuilder.build(CalendarBuilder.java:147)
2007-11-15 12:40:22.050999500 at com.atlassian.confluence.extra.calendar.ical.model.ICalCalendar.readFromSource(ICalCalendar.java:445)
https://support.atlassian.com/browse/CSP-13271