Unable to Correct Calendar App's Time Zone

I can't correct the Time Zone in my Calendar app. I am trying to switch it back to Eastern Time but it keeps reverting to UTC in the drop menu and when I create a new or update an existing event.

I check the Date and Time in the System Preferences and it is correct. So why is the Calendar app behaving this way?

I don't know what version of Calendar you are using, but on my version you change timezones in the upper right corner of Calendar, where you click on the current time zone then "Other" and a map of the world opens and you click on the timezone you want, then pick the nearest city. Under Preferences, Advanced I also have a check mark in "Turn on time zone support."

Does that not work for you? What version of Calendar? What OS? I'm using Mavericks, Calendar 7.0.

I am running Mountain Lion 10.8.5. The Calendar app is 6.0. Sorry if I was not clear in describing the steps I tried. But yes, I did attempt to change the time zone in the upper right corner of the Calendar app. It just doesn't want to accept the modification. Isn't the Calendar app suppose to sync with the Date and Time setting?

Is it possible that someone hacked into my home network in some manner? I can't think of any other reason.

I doubt anybody hacked into your network, but you should have the network set to require login and use WPA, WPA2 or WPA Personal as the encryption.

On the Calendar, I believe it get the date and time from the system, but you set the TZ in the app. When you say it "doesn't want to accept the modification," what do you mean? Do you get an error message? I'm on version 7.0, as I said, but basically all it does is allow you to pick the zone, nearest city and then click OK to set that zone as the default TZ. When I close Calendar and then reopen it, it comes back to the set zone, but if I open the Other setting again, it shows Cupertino, CA as the default suggestion, but Eastern Zone as my setting.

When I make the change to the Time Zone in the upper right hand corner drop menu of the app, close the dialog box and double check it gain, it seems to stay on Eastern Time. When I create an event, it will initially say UTC for the Time Zone. I change it to Eastern, then save and close the event. I re-open it and it switches back to UTC.

On a separate test without creating an event, I make the change in the upper right corner drop menu of the app, double check to make sure it says Eastern. When I close the app and re-launch, it jumps back to Cupertino, CA. Always that location.

There is no error message in either case. It just changes or defaults back on it's own.

Is Apple doing some behind the scenes here? I am mean Apple is located in Cupertino, CA.

Do you have the check for Time Zone support I mentioned in my first post?

Under Preferences, Advanced I also have a check mark in "Turn on time zone support."

Click to expand...

From what I can read in the help for Calendar, if that is not checked, the time will be the internal system time, which is always UTC. From UTC, the OS calculates the current date/time to your timezone set in System Preferences/Date & Time/Time Zone. I don't think that setting then feeds Calendar, as it has its own setting for TZ.

As for the default to Cupertino, that's definitely not by accident. The world revolves around Cupertino, at least in Apple's world!

As I said, if I check right after setting it, the TZ shows Eastern on the map, but if I close and then re-open Calendar and go to "Other" it defaults to Cupertino as the suggestion. That's normal behavior. So I think if you check the "Turn on time zone support" box you'll get what you want.

Further update. I just tried restarting my computer and even disconnecting all external services (Internet and Wi-Fi) and unplugged the Ethernet cable. No difference. Time Zone support is usually on but I also tried it off as a test to see if this would shake something loose. But of course it will not be an option when you create an event.

I did notice one odd thing. When I make the change in the upper right hand drop menu of the Calendar app, it will display the supposed time zone that I changed it to. When I check it again, it will still reflect the change. When I relaunch the app, the specific time zone is still listed. But once I access the drop menu, it says Cupertino.

I tried setting it to any location and it still jumps back to Cupertino without any warning.

I have other email accounts google and a work one. Could they be affecting the Time Zone of the Calendar in some way? I already checked my router and the Time Zone is correct.

This is perplexing to put it mildly.

Let me try again, I'm not saying it clearly enough.

When you start Calendar, the current setting for timezone is shown in the upper right corner of the Calendar window. In my case, it says "Eastern Time." When you click on that time zone name, a box opens that offers "Other." If you choose that, a map opens of the world with the Pacific timezone highlighted and Cupertino as the suggested city. If you simply click "Cancel" the timezone in the upper right corner of the Calendar window remains Eastern Time. If you click on a different zone on the map when it is open and select a different city in that zone, and then click on "OK" then the timezone shown in the upper right of the Calendar window changes to that new timezone. If you now click on "Other" again, the map shows your most recent choice that you OK'd. But if you close Calendar and then reopen it, although the upper right hand corner of the window shows your most recently chosen Timezone, if you click on Other the map opens with the highlighted timezone as Pacific and the city as Cupertino. That's how it is designed. That's normal. Apple assumes that if you have just started Calendar and click on Other that you want to change timezones, so they "helpfully" default to Pacific and Cupertino because that's where THEY are, no other reason. But if you have changed TZ in this session of Calendar they show what you selected. So, basically, if you pick "Other" from a fresh start of Calendar, it goes to Cupertino, but if you pick "Other" after setting the timezone in that session, it stays on what you just selected. No matter what, you must click on OK to actually change the timezone setting.

Connections have ZERO to to with timezones, except that the OS determines UTC from connections to certain time servers on the internet and if you tell it to automatically set the TZ from your location, it will adjust based on your IP. From UTC, it calculates your local time for the system from the System Preferences/Date & Time/TimeZone setting. However, the default TZ for Calendar operations should be from the setting shown in the upper right corner of the Calendar window. The rationale for that function is that while the clock UTC doesn't ever change location (UTC is UTC, always) you may move to or live in a different time zone, so you get to set your system clock display and calculations using the System Preferences. In Calendar there is another complication in that you may receive invitations, or send invitations, from and to other TZs, so it's important to be able to have the time shown properly on your calendar. That's why Calendar has a separate setting for the TZ you want it to use, and if you check the Calendar Preferences box for "Turn on time zone support" then you can have your calendar adjust as you receive invitations from other time zones by setting it in System Preferences for Calendar. So if your friend in London UK sends you an invitation for a meeting at 3 pm in London and you live in Virginia with Eastern Time selected in Calendar and time zone support turned on, the invitation will post to your Calendar at 10 am EST. Note that 3 PM London time and 10 AM Eastern time are both 3PM UTC (Actually it's 1500 UTC, but I don't want to get into 24 hour time here!)

So, I can travel from my home in Virginia to London, UK, for example and if "Set time zone automatically" is checked, when I boot my machine and connect to the internet, my clock will update and my TZ will update to match my perceived location based on my IP address. So my local clock will show London time, not Virginia Time. If I open Calendar, it will still show Eastern time in the upper right corner because that is what I chose. What will be on my calendar will be my appointments in EASTERN time, not UK time. To get them to show in UK time, I have to click on "Other" and select the time zone for London, UK. Then I reverse all that when I return to Virgina.

Clear as mud? Time is a complex subject in computing and the idea is to give you flexibility to enter data without having to do the calculations from UTC yourself. The system does it for you.