HTTP 500 internal server error during checkout

[valvoj]

Hello,
I'm testing my site on v1.5.0. Currently running fine on v1.3.9h. I upgraded it and working except for checkout. Once you click on "go to checkout" or "checkout with PayPal" when logged in I get the http 500 internal server error message.
My site is g u a r d i a n a n g e l s o c. org/ zencart150

Our host is Godaddy. I checked a copy of the log and only thing I see in it that is relevant is:
108.x.x.x. - - [31/Oct/2012:08:47:01 -0700] "GET guardianangelsoc.org/zencart150/index.php?main_page= HTTP/1.1" 200 23433 "http://guardianangelsoc.org/zencart150/admingas/modules.php?set=shipping&module=usps" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)"
108.x.x.x. - - [31/Oct/2012:08:47:04 -0700] "GET g u a r d i a n a n g e l s o c /zencart150/index.php?main_page=shopping_cart HTTP/1.1" 200 18640 "http://g u a r d i a n a n g e l s o c /zencart150/index.php?main_page=" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)"
108.x.x.x. - - [31/Oct/2012:08:47:06 -0700] "GET g u a r d i a n a n g e l s o c .org/zencart150/index.php?main_page=checkout_shipping HTTP/1.1" 500 - "http://g u a r d i a n a n g e l s o c /zencart150/index.php?main_page=shopping_cart" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)"


Any thoughts?

[valvoj]

Nevermind, figured out what the issue was after looking at some other threads. When running the site in Firefox I got just a blank page. So, I then found this thread http://www.zen-cart.com/content.php?124-blank-page

That helped to have me look at my cache logs which mentioned an error in \includes\classes\order.php which then led me to this thread: http://www.zen-cart.com/showthread.p...re+class+order
where the actual issue was the renaming of header_php.php in /includes/modules/pages/checkout_shipping/