Server is in Mountain Standard Time and is hosted by Godaddy on a Virtual Dedicated Server. I confirmed with Godaddy Staff that they house those somewhere near Phoenix, AZ USA.

In my configuration.php file, as of 2 days ago I have set...

public $offset = 'America/Phoenix';
public $offset_user = 'UTC';

beat and I went over that two days ago. Initially and mistakenly, I did have it set for Los Angeles.

Interesting, could you please contact your host and ask if they're doing rolling restarts on their server? Some/most hosts do a restart every day at a set time. Can't really think of why this would be happening. Is any caching enabled (Joomla or Server side)? The session issue is rather on-going for many releases, but we've never been able to pinpoint the cause.

I get a SMS message each time my server restarts. It rarely does. Being Virtual Dedicated, I have ability to restart the server whenever I need to.

Caching is disabled...

public $caching = '0';
public $cache_handler = 'file';
public $cachetime = '15';

I have thought about changing cachetime to 0 even though caching is already 0, just to see what would happen.

Can you give me some examples of "server side" caching? I use cPanel Web Host Manager (WHM) on the server and create sub cPanel hosting accounts for each of my businesses.

I have a prediction that I will encounter this error at 4:00 PM today my time and not a moment sooner. I will tell you why. The GMT date will change at 4:00 PM today to February 5th, whereas I and my server will still be in February 4th.

Somewhere in your session handler, you are probably comparing date/time based on time alone, assuming the date is the same, but since there is a mismatch of the day it produces an error.

Furthermore the error seems to go away after 11:00 PM my time, which is 12:00 AM my server's time which is a new calender day that matches what GMT's day currently is.

I bet if I change my servers time to GMT and my Joomla time to GMT, the error will go away. I can easily test this.

Are there any error logs I can turn in to you that would give you any indication what is going on?

I see, have a good idea on how to test this and will look deeper into the issue. We've already a bug ticket for session errors and will add this thread to the ticket if not done already.

#2283 - forge.joomlapolis.com/issues/2283

I see you found the issue is residing in Joomla 1.6 from the looks of your last update to the bug in your bug tracker. Nice!

I went ahead and changed the timezone on my server to GMT and Joomla to UTC for now so i wont be affected by this and can continue to develop after 4:00 PM till 11:00 PM.