I need your help. My user got this error while trying to post and clear invoices with a payment with transaction code F-26. I've never seen this error before. I did some research in the network and I saw that this error is commonly caused by intercompany postings but all my invoices, albeit in 2 different customer belong within the same company code.
Check the GL view of the customer open items that your user is attempting to clear. One of the open items has a blank trading partner (VBUND) and another one has SMX000 as the trading partner. Here is an example:
Open item 1: Dr. Customer $100 (Trading partner field is blank)
Open item 2: Dr. Customer $ 50 (Trading partner field is filled with value SMX000)
Now, when F-26 attempts to clear the above open items (you are using document type DZ, lets say), here is the entry:
Dr. Bank $150
Cr. Customer $100 (Trading partner blank)
Cr. Customer $50 (Trading partner SMX000)
System cannot post the above document, because you have multiple trading partners within the same document, and document type DZ does not allow multiple trading partners.
You have two choices:
1. Try clearing these open items individually.
2. Check the checkbox 'Inter-company postgs' for document type DZ (or any other document type that you are using in F-26) in T Code OBA7.