Possible Email Fields

-- HikaShop version -- : 2.2.2
-- PHP version -- : 5.3.28
-- Error-message(debug-mod must be tuned on) -- : The following from address failed :adminArtis@secretheadquartersartstudio.com: Mail not accepted from server, 55), From address must match authenticated address.
SMTP server error: From address must match authenticated address
SMTP server error: From address must match authenticated address

I have spent hours trying discover where This email address is being protected from spambots. You need JavaScript enabled to view it. is being pulled from but I'm unable to find it anywhere.

My cart checkout process is:
Cart
Terms/Condition
Payment
Status

This issue happens has soon as click Finish under payments
The email error message comes up
Then customer is sent to PayPal.

Joomla configuration - Mail server is using admin@secret.....
My Contact form has a contact - uses admin@secret....

HikaShop Configuration
System Configuration:
From Address: admin@secret
Reply-to-Address: admin@secret
Payment Notifications: admin@secret
Order Creation: admin@secret
PayPal pluggin has admin@secret

I'm wondering if this is an old cached file or is there another spot in HikaShop where this email could be hiding out and I'm missing it.

Any assistance would be appreciated.

Awesome - thank you Nicolas. It was only after your reply did I even notice the tab option for each tab. HikaShop is working fine now.