YAALP - Yet another admin login problem

[Slack]

I recently had an issue where I was unable to login to my production Zen Cart 1.3.7 installation. After trying several things I decided to try a fresh install on the same server. This did not help. Thanks in advance!

Slack

Here are the details:

Problem
When attempting to login via the admin/login.php page, the page appears to accept the valid login credentials and then the browser (IE 7) returns an error "Internet Explorer cannot display the webpage...". In addition it appears that new users can register, but they are unable to log in.

I have worked through the following tutorials and have not found a resolution.
http://tutorials.zen-cart.com/index.php?article=82
http://tutorials.zen-cart.com/index.php?article=84
http://tutorials.zen-cart.com/index.php?article=281

The current install was done from a 1.3.8a installation .zip downloaded today and using the zc_install folder. No issues were left identified during the installation. The only problems encountered during installation were the typical ones with file permissions.

Environment
Host: 247-host.com
OS: Linux (kernal 2.6.9-67.ELsmp)
PHP: 5.2.3
Apache: 2.0.63
MySQL: 4.1.22-standard

Zen Cart configuration
Zen Cart URL: http://www.pillarcom.com/zen
SSL: off
admin user: kilgore
admin pass: admin (test system, no worries)
user: kilgore@pillarcom.com
user pass: password (test system, no worries)
Admin URL: http://www.pillarcom.com/zen/admin/login.php
config files: see attached or
http://www.pillarcom.com/zen/includes/configure.html
http://www.pillarcom.com/zen/admin/i...configure.html
phpinfo: http://www.pillarcom.com/zen/phpinfo.php
cache folder: world read,write,execute - able (777)