GATP - Third Party Order Processing (TPOP)

Hi Gurus,

I am trying to setup TPOP scenario.This is what I have done till now :

1. Vendors and standard info records CIFed across to APO
2. Product created in vendor location.Active version assigned,check mode and ATP group assigned
3. Check instructions with 'Source determination directly' and method 'Check against info records'
4. Requirements profile created

When I create the sales order on a plant,the availability check result shows as vendor selected.

But when I am about to save the result,I get the below error :

Maintain plant 0000 for the sales area

Message no. V1762

Diagnosis

No sales area data has been entered for plant 0000, or the data is incomplete. However, this sales area data is required for the current cross-company code sales transaction.

System Response

The system cannot execute the current sales transaction.

Procedure

In the "Define Shipping Data for Plants" Customizing activity under Materials Management (Purchasing), enter a sales organization, a distribution channel, and a division for intercompany billing for plant 0000

I understand system is trying to create a purchase order on the vendor.

What and how I configure the above in ECC ?

Any additional steps required for TPOP ?