Diagnosis
The partner does not exist or has not been assigned to the partnercompany code.

Procedure
Select a partner valid for this company code.
To create a valid partner, proceed as follows:
Create the partner as a customer in Financial Accounting.
Assign the partner company code to the partner using transactionEdit Joint Venture Partner .
If the joint venture partner is an internal partner and not a corporatepartner, assign (as partner company code) the company code in whichthis partner is entered into the system.
If the joint venture partner is an external partner, there is nopartner company code. The partner company code is initial, in otherwords, you leave the entry in the partner company code blank.
If the joint venture partner is acorporate partner assign the companycode (as the partner company code) in which the corporate partner isused.