Fix this issue by auto updating admin IP address when they login.
Opencart 126.96.36.199 restricts API access by IP adresses stored in the database. Unless you have a static IP address you will find your dynamic IP address will constantely need updating.
Error message when trying to edit order:
Warning: Your IP * is not allowed to access this API!Setup
- Installing modification
- Refresh modifications
- Go to API acess form and select the admin user. Create an API access for each admin user.