Hello,
What is company TEST in this message? Is this a multi-company supplier invoice? 

TEST is the name of the company in TEST environment. I am trying different options in TEST environment.

This is not a multi-company supplier invoice.

I was thinking IDEKO is company name, as visible in invoice window title bar? 

Sorry, I mixed different screenshots and it was confusing.

This is the message I get in PROD environment when I try to cancel the real posted supplier invoice.

Any idea of how to cancel it?.

Hello,

The only possible issue I can remind in such a case would be invoice forwarding - do you have IFS Project module in use? Perhaps cost from invoice have been forwarded to project cost transaction and this transaction is reimbursed - billed to the customer. I think this error message is generated by project transaction - when it is deleted during cancellation of source invoice. 

Is it the case? 

If not, detailed investigation would be required, perhaps support case needed.

Yes, we use the Project module.

The cost of the invoice is charged to the project.

The project_id in the invoice is not the correct one and that’s why we want to cancel it and cancel the purchase order, and start again with the correct project_id.

OK, so please check status of project transaction created by the supplier invoice on the incorrect project - perhaps it is included in customer invoice.

Yes, the supplier invoice is included in customer invoice and it is posted, so I can’t delete it.

I have tried with another test example, and deleting the customer invoice (which was not posted), I have been able to delete the posted supplier invoice.

But with my real case, I can create a credit invoice for the customer, but I don’t know how to discharge the supplier costs to the project.

Well, you have multiple possibilities:

• you can try to reverse all incorrect operations: use option of crediting customer invoice (as it is obviously incorrect, containing costs from another project...) disconnecting project transaction from invoice this way, then cancel and recreate supplier invoice should be possible and you will be able to create customer invoice again with correct content.
• You can create 2 dummy supplier invoices - positive on correct project and negative on incorrect one. Forwarding them to projects you will receive negative and positive project transactions to be invoiced/credited to customer.
• You can use manual voucher to reclass invoice final entry and create corresponding project invoices manually.

Choice is yours, depending on the significance of the issue...

Thank you very much for your help, Adam.

About the possibilities you mentioned, I think the first option would be the best for us, but even I create the credit custormer invoice, the application doesn’t let me to cancel the supplier invoice. The same message error appears.

So, I will create 2 dummy supplier invoices as you said, one positive on correct project and one negative on the incorrect one.

Best regards,

Amaia