iMac detecting wrong time zone!

I don't know why this has happened but deselect "set time zone automatically using current location" and once you correct it again it will more likely stay that way.

It is probably not related but I heard Egypt has cancelled their daylight saving, so maybe some changes being made to the time server is affecting you as well.

Hello f:

In system preferences>date & time (and then click on date & time) the box to set it automatically should be checked. Have you tried selecting a different server from the drop-down menu?

In the same area, click on "time zone." That box is, in my case, unchecked as my computer is not moving around.

You might also (if the above does not help), try trashing a preference file (com.apple.timezone.auto.plist) and restarting.

Barry

My understanding is that if the "Set time zone automatically" box is checked, Snow Leopard tries to determine its current location, a feature not present in earlier OS versions. This is not trivial because a Mac doesn't have a GPS chip or a cellphone chip, and I believe all the time servers send their time signals as Universal Time. A Mac does have a wi-fi card, and can detect nearby wi-fi networks. If the worldwide location of a large number of wi-fi signals had been previously mapped and stored in an Apple database, Snow Leopard could compare its own currently detected wi-fi signals with this database and so determine its current location. Apple initially used a company called Skyhook for the wi-fi mapping database, but I believe Apple is now doing this in-house.

So in your situation it may be that Snow Leopard's Location Services is getting confused because it is now detecting a nearby wi-fi signal that an online database had previously mapped as being in Korea! Do you have any new neighbors who might have just moved from there and brought their wi-fi router with them?!

Operationally, until Apple's central location database is updated there's probably nothing to do except to keep the "automatic" box unchecked.

My understanding is that a wi-fi hotspot broadcasts a unique identifier number, and you can "detect" this identifier without actually connecting to the hotspot's network. No transmitted data is intercepted. Here's an early news article about Skyhook's initial use in iPhones that explains how it works.

http://www.nytimes.com/2009/06/01/technology/start-ups/01locate.html

As I mentioned, I think Apple now uses its own location database of wi-fi hotspots and cellphone towers.

It's not really clear, though, that a central database error is the cause of your problem, particularly since it happened suddenly. There still could be something wrong with your iMac system, possibly a corrupted cache file used by Location Services. I see from your profile that you also have a MacBook Air. When it is in the same room as your iMac, does the MacBook Air show the same automatic time zone error?

You could try going to System Preferences>Security>General, check the box for "Disable Location Services", and restart. Then go back to the same Preference screen and uncheck that same "Disable Location Services" box.

If that doesn't work, I'm about out of ideas short of re-installing the OS, which I wouldn't bother with since this is essentially a cosmetic issue. Your times should remain accurate since you should still be able to keep the box checked for "Set date and time automatically" in the "Date and Time" tab of System Preferences> Date &Time. Just don't check the "Set time zone automatically" box in the Time Zone tab.