the timezones.properties has a missing timezone: Europe/London This means that on a system (like ours) where the default timezone of the VM in Europe/London then this happens: java.lang.StackOverflowError at java.util.HashMap.containsKey(HashMap.java:377) at com.atlassian.confluence.core.TimeZone.getInstance(TimeZone.java:37) at com.atlassian.confluence.core.TimeZone.getDefault(TimeZone.java:112) at com.atlassian.confluence.core.TimeZone.getInstance(TimeZone.java:39) at com.atlassian.confluence.core.TimeZone.getDefault(TimeZone.java:112) at com.atlassian.confluence.core.TimeZone.getInstance(TimeZone.java:39) on any page. Looking at the source of com.atlassian.confluence.core.TimeZone I note tht the timezones are loaded from a timezones.properties file. Europe/London is missing from this properties file. Adding Europe/London fixes the issue.. Why not remove the properties file though,, and modify com.atlassian.confluence.core.TimeZone to be: private static Map loadTimeZones() { String[] timeZoneIDs = java.util.TimeZone.getAvailableIDs(); Map result = new HashMap(timeZoneIDs.length); for (int i = 0; i < timeZoneIDs.length; i++) { String timeZoneID = timeZoneIDs[i]; result.put(timeZoneID, new TimeZone(timeZoneID)); } return result; } so that all timeones are loaded???