500 Internal Server Error - Applied SUPEE-7405 1.0, 1.1

[paul_c]

Hey Guys,

I'm having crazy issues on checkout page:

500 Server error on /checkout/onepage/progress/?toStep=shipping_method

sometimes on billing too.

Its completely random, sometimes it shows up, sometimes not.

SUPEE 7405

I have applied both 1.0 and 1.1 via FTP, but the issue with checkout still persists!

Please help!

[paul_c]

A few updates:

Both MCRYPT,MBSTRING and SOAP are enabled on the server. I'm running PHP 5.4.45 with APC 3.1.13 on 1230 Intel CPU, 16GB of RAM, 2TB Drives

Update:

Chrome Console spits this out:

prototype.js:1530 POST /checkout/onepage/saveBilling/ 500 (Internal Server Error)

Ajax.Request.Class.create.request @ prototype.js:1530 Ajax.Request.Class.create.initialize @ prototype.js:1495 (anonymous function) @ prototype.js:429 klass @ prototype.js:101Billing.save @ /skin/frontend/base/default/js/opcheckout.js:313 onclick @ /checkout/onepage/:679

UPDATE: Apache Logs have these types of errors:

24.87.30.186 - - [21/Apr/2016:16:13:43 -0700] "POST /checkout/onepage/saveBilling/ HTTP/1.1" 500 - "https://www.example.com/checkout/onepage/" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36"

216.129.65.170 - - [21/Apr/2016:16:08:00 -0700] "GET /checkout/onepage/progress/?toStep=payment HTTP/1.1" 500 461 "https://www.example.com/checkout/onepage/" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36"

216.129.65.170 - - [21/Apr/2016:16:08:00 -0700] "GET /checkout/onepage/progress/?toStep=payment HTTP/1.1" 500 461 "https://www.example.com/checkout/onepage/" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36"

[Pronto]

This is almost certainly PHP fatal error / exception. Check PHP logs.

[vishal_anil]

1.) check /var/report and latest report entries when you get that error . that will guide you . 

2.) disable apc and check if you are still receiving the same error . 

3.) check applied.patch.list file in /app/etc/ to find out if the 7405 is applied successfully - which files have been patched and replaced  . verify it with your backups .