ProtX - Error with VSP Form Payment Gateway

[RedQuince]

Having set up the vendors, product categories, products, etc. as per the help text, I have tried to process a purchase.  The following error is displayed:

 
Fields in your VSP Form Submission POST
The following fields were included in the FORM sent to the VSP Form submission page.
VPSProtocol: 2.22
TxType: PAYMENT
Vendor: [not present]
Crypt: Present - See decoded section below
Submission Errors
You did not provided a VSP Vendor Name in the Vendor field of the transaction registration POST.
 
I have re-checked all information and can not work out where the VSP Vendor Name is stored.  Any ideas?

Thank you.

[netshine]

It is in the gateway settings page. Go to Front End->Payment Gateways, and click on ProtX.

[RedQuince]

That seems to have dome the trick.  Thank you.