Perhaps you might get more help if you supplied pertinant information like:
- version of Zen Cart
- version of PHP
- is this an Apache server, or IIS
- list of any contributions installed
- list of customizations made
- is your site running in SSL mode or not
- is authorize.net in test mode or production mode, both in Zen Cart and in your Merchant terminal settings
- what errors are appearing in your server's errorlog
- what browsers are you using for testing
- what is the exact URL you're seeing that "does not" work, and the exact URL that "does" show order details
- on the page the shows incomplete information, what *does* show on the page?