Warning change time zone identifier now can't login into admin area

For some reason my cart has been changing internally, meaning the scripts. I have tried to login and I am receiving this message:
Warning: strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CST/-6.0/no DST' instead in /home/erbornb2/public_html/tammy/login.php on line 13
Don't have a clue why this is happened maybe my hosting server is having problems, I tried following this path but could not see the time zone identifier on line 13 in login.php?
Thanks
Ron

RonGin:

For some reason my cart has been changing internally, meaning the scripts. I have tried to login and I am receiving this message:
Warning: strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CST/-6.0/no DST' instead in /home/erbornb2/public_html/tammy/login.php on line 13
Don't have a clue why this is happened maybe my hosting server is having problems, I tried following this path but could not see the time zone identifier on line 13 in login.php?
Thanks
Ron

Suggest changing your secret admin directory now that it has been posted....

https://docs.zen-cart.com/user/new_user_topics/timezone

RonGin:

For some reason my cart has been changing internally, meaning the scripts. I have tried to login and I am receiving this message:
Warning: strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CST/-6.0/no DST' instead in /home/erbornb2/public_html/admin/login.php on line 13
Don't have a clue why this is happened maybe my hosting server is having problems, I tried following this path but could not see the time zone identifier on line 13 in login.php?
Thanks
Ron

Could edit includes/extra_configures/set_time_zone.php
to reflect your timezone, ie CST:
(The code includes a website reference to locate the applicable timezone information.)

if (version_compare(PHP_VERSION, 5.3, '>='))
{
  // put your timezone here. Refer to http://www.php.net/manual/en/timezones.php
  $TZ = 'America/Chicago';  // eg: 'Europe/Oslo'



  /**
   * MAKE NO CHANGES BELOW THIS LINE
   *

Thank you both for your advices, I have tried both and I am still getting the error message. So I guess I will contact dierctnic now.
Ron