Time zone auto isn't working
For my last few updates (I'm only on 10.9.5) my air ignores the checkbox to set date and time automatically. It does put a pin on my correct city (I go back and forth between EST and MST) but whichever time zone I came from remains the time unless I manually relocate it. This wasn't happening a few upgrades past. Any suggestions?
And this is a late 2011 MB Air with 4 gigs of memory and a 1.8 Ghz Core i7. Do I have the horsepower to run Yosemite? I'm a bit reluctant to upgrade again and lose more functionality, as I did the last time.
MacBook Air, Mac OS X (10.7.5)